Code Center

To change the background color or to change the inner text of a item in dropdown

2010-06-03T05:19:00.000-07:00

To change the background color or to change the inner text of a item in dropdown

// Loop around the dropdown
for (row = 0; row < ddlUserName.Items.Count; row++)
{
// To color a particular user name
if (ddlUserName.Items[row].Value == this.USERID.ToString())
ddlUserName.Items[row].Attributes.Add("style",
"background-color:" + "#663333;color:#ffffff;");
}

Gridview headertemplate with checkbox and client side ( javascript) handling of select all / unselect all

2010-06-02T22:50:00.000-07:00

Gridview headertemplate with checkbox and client side handling of select all / unselect all using javascript.
courtesy from
http://dotnetslackers.com/Community/blogs/kaushalparik/archive/2008/07/16/checkbox-in-headertemplate-to-select-all-checkboxes-inside-a-gridview-using-javascript.aspx

Idea and code from this site, I enhached and made small corrections this for my application, according to my requirement

Thanks to http://dotnetslackers.com/ for all the code.


        <div>

        <input type="hidden" id="hdnCheckBoxValue" />

            <table>

                <tr>

                    <td style="width: 100px;">

                        <asp:GridView ID="gvVendorBulletin">

                            <Columns>

                                <asp:TemplateField ItemStyle-HorizontalAlign="Center" ItemStyle-VerticalAlign="Middle"

                                    HeaderText="" ItemStyle-BorderWidth="0">

                                    <ItemTemplate>

                                        <asp:CheckBox ID="chkItem" runat="server" onclick="VendorItemSelected(this)" />

                                    </ItemTemplate>

                                    <HeaderTemplate>

                                        <asp:CheckBox ID="chkHdrItem" runat="server" onclick="VendorSelectAll(this)" />

                                    </HeaderTemplate>

                                </asp:TemplateField>

                            </Columns>

                        </asp:GridView>

                    </td>

                </tr>

            </table>

        </div>



<script language="javascript" type="text/javascript">

function callFileDownload(a,b)

{

  function callCheckAllVendor(CheckBox) {



            TotalChkBx = parseInt('<%= this.gvVendorBulletin.Rows.Count %>');

            var TargetBaseControl = document.getElementById('<%= this.gvVendorBulletin.ClientID %>');

            var TargetChildControl = "chkItem";

            var Inputs = TargetBaseControl.getElementsByTagName("input");

            var flag = true;

            document.getElementById("hdnCheckBoxValue").value = true;

            for (var iCount = 0; iCount < Inputs.length; ++iCount) {

                if (Inputs[iCount].type == 'checkbox' && Inputs[iCount].id.indexOf(TargetChildControl, 0) >= 0) {

                    if (!Inputs[iCount].checked) {                       

                        flag = false;

                        document.getElementById("hdnCheckBoxValue").value = false;

                        return;

                    }

                }

            }           

        }

        function VendorSelectAll(CheckBox) {

            TotalChkBx = parseInt('<%= this.gvVendorBulletin.Rows.Count %>');

            var TargetBaseControl = document.getElementById('<%= this.gvVendorBulletin.ClientID %>');

            var TargetChildControl = "chkItem";

            var Inputs = TargetBaseControl.getElementsByTagName("input");

            for (var iCount = 0; iCount < Inputs.length; ++iCount) {

                if (Inputs[iCount].type == 'checkbox' && Inputs[iCount].id.indexOf(TargetChildControl, 0) >= 0)

                    Inputs[iCount].checked = CheckBox.checked;

            }

        }

        function VendorItemSelected(CheckBox) {



            TotalChkBx = parseInt('<%= this.gvVendorBulletin.Rows.Count %>');

            var TargetBaseControl = document.getElementById('<%= this.gvVendorBulletin.ClientID %>');

            var TargetChildControl = "chkHdrItem";

            var Inputs = TargetBaseControl.getElementsByTagName("input");                       

            if (!CheckBox.checked) {

                for (var iCount = 0; iCount < Inputs.length; ++iCount) {

                    if (Inputs[iCount].type == 'checkbox' && Inputs[iCount].id.indexOf(TargetChildControl, 0) >= 0)

                        Inputs[iCount].checked = CheckBox.checked;

                }

            }

            else {

                callCheckAllVendor(CheckBox);               

                var flags;

                if (document.getElementById("hdnCheckBoxValue").value == "true") {

                    flags = true;

                }

                else {

                    flags = false;

                }

                for (var iCount = 0; iCount < Inputs.length; ++iCount) {

                    if (Inputs[iCount].type == 'checkbox' && Inputs[iCount].id.indexOf(TargetChildControl, 0) >= 0)

                        Inputs[iCount].checked = flags;

                }

            }

        }

}

</script>

Dynamically add CommandField of type Image to a gridview or any container.

2010-06-02T22:28:00.000-07:00

Kindle Wireless Reading Device (6" Display, Global Wireless, Latest Generation)

Dynamically add CommandField of type Image to a grid or any container.

if (!IsPostBack)
{
if (Session["USERTYPE"].ToString() == "S")
{
CommandField ImageCommand = new CommandField();
ImageCommand.ButtonType = ButtonType.Image;
ImageCommand.DeleteImageUrl = "~/images/delete.gif";
ImageCommand.ShowCancelButton = false;
ImageCommand.ShowDeleteButton = true;
GridView1.Columns.Add(ImageCommand);
}
}

Then do the normal

protected void GridView1_RowDeleting(object sender, GridViewDeleteEventArgs e)
{

}

to delete or change as per your requirements.

A New Operating System from GOOGLE: IS that a Downfall to WINDOWS?

2009-07-08T23:54:00.000-07:00

Google is about to introduce a new OS in the middle of 2010, is that meant to compete the giant Windows?, Is that to be a David to Windows?

Read further:

Google Blog

Economic Times

It's Time to Get Good at Functional Programming

2008-12-10T01:08:00.000-08:00

It's Time to Get Good at Functional Programming

Linux Clone of Microsoft's Silverlight in Beta

2008-12-08T06:03:00.000-08:00

Linux Clone of Microsoft's Silverlight in Beta

To get the query string through javascript (Client side)

2008-12-08T05:46:00.000-08:00

window.location.search.substring(1);

Google unleashes unlocked G1 on developers

2008-12-07T22:11:00.001-08:00

Google unleashes unlocked G1 on developers

To get the email addresses from aliases names : Outlook Programming using C#

2008-11-26T21:17:00.000-08:00

Breach of Trust

To get the email addresses from aliases names : Outlook Programming using C#
IDE : Visual Studio 2008

Please ignore inappropriate content as put entire code since I am adding some more functionality other than finding the address through aliases names.

using System;
using System.Collections.Generic;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Microsoft.Office.Interop.Outlook;
using System.Runtime.InteropServices;
using System.IO;
using ObjOutlook = Microsoft.Office.Interop.Outlook;

namespace Stmp_Client_2008
{
public partial class Form1 : Form
{
public String MailsSub;

public String Cc;
public String To;
public String Bcc;
public String SenderMailAddr;

private static ArrayList emailCollection = new ArrayList();
public static Boolean SuccMail = false;
public static Boolean MailFlag = false;

ObjOutlook.Application App = new ObjOutlook.ApplicationClass();
ObjOutlook.NameSpace NS;
ObjOutlook.MAPIFolder CheckFold;
ObjOutlook.MAPIFolder MovingFold;
ObjOutlook.MAPIFolder ErrMovingFold;

const int S_OK = 0;

[DllImport("MAPI32.DLL", CharSet = CharSet.Ansi, EntryPoint = "HrGetOneProp@12")]
private static extern void HrGetOneProp(IntPtr pmp, uint ulPropTag, out IntPtr ppProp);

[DllImport("MAPI32.DLL", CharSet = CharSet.Ansi, EntryPoint = "HrSetOneProp@8")]
private static extern void HrSetOneProp(IntPtr pmp, IntPtr pprop);

[DllImport("MAPI32.DLL", CharSet = CharSet.Ansi, EntryPoint = "MAPIFreeBuffer@4")]
private static extern void MAPIFreeBuffer(IntPtr lpBuffer);

[DllImport("MAPI32.DLL", CharSet = CharSet.Ansi)]
private static extern int MAPIInitialize(IntPtr lpMapiInit);

[DllImport("MAPI32.DLL", CharSet = CharSet.Ansi)]
private static extern void MAPIUninitialize();

const string IID_IMAPIProp = "00020303-0000-0000-C000-000000000046";
const uint PR_SMTP_ADDRESS = 972947486;

public struct SPropValue
{
///

/// Property tag for the property. Property tags are 32-bit unsigned integers consisting of the property's unique identifier in the high-order 16 bits and the property's type in the low-order 16 bits.
///

public uint ulPropTag;

///

/// Reserved for MAPI; do not use.
///

public uint dwAlignPad;

///

/// Union of data values, the specific value dictated by the property type.
///

public long Value;
}

public Form1()
{
InitializeComponent();
}

private void Form1_Load(object sender, EventArgs e)
{

}
private ObjOutlook.MAPIFolder GetFolder(ObjOutlook.Folders ReadFold, string name)
{

ObjOutlook.MAPIFolder TempStr = null;

foreach (ObjOutlook.MAPIFolder MovFold in ReadFold)
{
if (MovFold.Name == name)
{
TempStr = MovFold;
}

if (MovFold.Folders.Count > 0)
{
ObjOutlook.MAPIFolder TempStr2 = null;

TempStr2 = GetFolder(MovFold.Folders, name);
if (TempStr2 != null)
{
TempStr = TempStr2;
}

}
}

return TempStr;

}

//From the URL http://weblogs.asp.net/cumpsd/articles/89697.aspx

private static void AddAddress(string emailAddress)
{

emailAddress = emailAddress.Trim();

emailAddress = emailAddress.ToLower();

if (!emailCollection.Contains(emailAddress))
{

emailCollection.Add(emailAddress);

}

} /* AddAddress */

private string GetEmailAddressFromExchange(string emailName)
{
ObjOutlook.MailItem loDummyMsg = (ObjOutlook.MailItem)App.CreateItem(ObjOutlook.OlItemType.olMailItem);
ObjOutlook.Recipient loAddress = loDummyMsg.Recipients.Add(emailName);
loAddress.Resolve();
string SMTPAddress = GetMAPIProperty(loAddress.AddressEntry.MAPIOBJECT, PR_SMTP_ADDRESS);

return SMTPAddress;
}

private string GetMAPIProperty(object oMAPIObject, uint uiPropertyTag)
{
if (oMAPIObject == null)
{
return "";
}

string sProperty = "";
IntPtr pPropValue = IntPtr.Zero;

IntPtr IUnknown = IntPtr.Zero;
IntPtr IMAPIProperty = IntPtr.Zero;

try
{
MAPIInitialize(IntPtr.Zero);

IUnknown = Marshal.GetIUnknownForObject(oMAPIObject);

Guid guidMAPIProp = new Guid(IID_IMAPIProp);

if (Marshal.QueryInterface(IUnknown, ref guidMAPIProp, out IMAPIProperty) != S_OK)
{
return "";
}

try
{
HrGetOneProp(IMAPIProperty, uiPropertyTag, out pPropValue);

if (pPropValue == IntPtr.Zero)
{
return "";
}

SPropValue propValue = (SPropValue)Marshal.PtrToStructure(pPropValue, typeof(SPropValue));

sProperty = Marshal.PtrToStringAnsi(new IntPtr(propValue.Value));
}
catch (System.Exception ex)
{
throw ex;
}
}
finally
{
if (pPropValue != IntPtr.Zero)
{
MAPIFreeBuffer(pPropValue);
}

if (IMAPIProperty != IntPtr.Zero)
{
Marshal.Release(IMAPIProperty);
}

if (IUnknown != IntPtr.Zero)
{
Marshal.Release(IUnknown);
}

MAPIUninitialize();
}

return sProperty;
}

private void button1_Click(object sender, EventArgs e)
{
NS = App.GetNamespace("MAPI");
CheckFold = GetFolder(NS.Folders, "Sample");
//MovingFold = GetFolder(NS.Folders, "HK_MailRead");
//ErrMovingFold = GetFolder(NS.Folders, "HK_ErrMail");

ObjOutlook.Items olmailItems = CheckFold.Items;
int iter=0;

try
{
//ObjOutlook.MAPIFolder ChkFld = NS.GetDefaultFolder(ObjOutlook.OlDefaultFolders.olFolderInbox);

if (CheckFold.Items.Count > 0)
{
// foreach (ObjOutlook.MailItem ListItem in ChkFld.Items)
//{
for (int iteration = 1; iteration <= CheckFold.Items.Count; iteration++)
{
ObjOutlook.MailItem ListItem = (ObjOutlook.MailItem)CheckFold.Items[iteration];

// }

MailsSub = ListItem.Subject;

if (MailsSub.ToLower().StartsWith("RE") || MailsSub.ToLower().StartsWith("Ka"))
{
//Cc = ListItem.CC.ToString();
//To = ListItem.To.ToString();
//Bcc = ListItem.To.ToString();
//SenderMailAddr = ListItem.SenderEmailAddress.ToString();
}

ObjOutlook.Items ioItems = (ObjOutlook.Items)CheckFold.Items;

string emailname;
string emailWithDomainName;

foreach (ObjOutlook.MailItem olMail in olmailItems)
{
foreach (ObjOutlook.Recipient olRecipient in olMail.Recipients)
{
// string address = olRecipient.AddressEntry.GetExchangeUser().Address.ToString();
try
{

emailname = olRecipient.Name;
emailWithDomainName = GetEmailAddressFromExchange(emailname);
emailCollection[iter] = emailWithDomainName;
iter++;
// ObjOutlook.ContactItem oCt = (ObjOutlook.ContactItem)olmailItems;
//string emaill = oCt.Email1Address.ToString();
}
catch { }
try { AddAddress(olRecipient.Address ); }
catch { }

}
}

try { Cc = ListItem.CC.ToString(); }
catch { }

try { To = ListItem.To.ToString(); }
catch { }
try { Bcc = ListItem.To.ToString(); }
catch { }
try { SenderMailAddr = ListItem.SenderEmailAddress.ToString(); }
catch { }

}
}
}
catch { }

for (int i = 0; i < emailCollection.Count; i++)
{
listBox1.Items.Add(emailCollection[i].ToString());
}

}
}
}

Happy Coding!!!

To create a User Control for add new rows dynamically using JavaScript, Asp.net, C#

2008-11-24T22:35:00.000-08:00

User Control Code

AddMore.ascx

<%@ Control Language="c#" Inherits="Ind.UC.AddMore" CodeFile="AddMore.ascx.cs" %>

<tr>

td>

tr>

td>

tr>

table>

function getObj(id) {

return document.getElementById(id);

}

function getAllValues(tableId)

{

var table = getObj(tableId);

var str="";

for(var i=1; i < style="">

{

str+="Row"+i+".value = ";

for(var j=0; j < style="">

{

for(var k=0; k <>

{

var childNode = table.rows[i].cells[j].childNodes[k];

if(childNode.type=="text")

str += "'"+childNode.value+"', ";

}

alert(str);

}

script>

AddMore.ascx.cs

namespace Ind.UC

{

using System;

using System.Web.UI.HtmlControls;

///

/// Summary description for AddMore.

///

public partial class AddMore : System.Web.UI.UserControl

{

//protected System.Web.UI.HtmlControls.HtmlInputButton btnDelete;

protected string clickEvent;

public string onclick {

get{return clickEvent;}

set{clickEvent = value;}

}

// private void Page_Load(object sender, System.EventArgs e) {

// // Put user code to initialize the page here

// }

#region Web Form Designer generated code

override protected void OnInit(EventArgs e) {

// CODEGEN: This call is required by the ASP.NET Web Form Designer.

InitializeComponent();

base.OnInit(e);

}

//Required method for Designer support - do not modify the contents of this method with the code editor.

private void InitializeComponent() {

//this.Load += new System.EventHandler(this.Page_Load);

//this.btnAddMore.Attributes.Add("onclick",this.clickEvent);

this.btnAdd.Attributes.Add("onclick", "javascript:addRowInATable('tblAddMorea')");

this.btnDelete.Attributes.Add("onclick", "javascript:deleteRowInATable('tblAddMorea')");

this.btnGet.Attributes.Add("onclick", "javascript:getAllValues()");

}

#endregion

protected void Page_Load(object sender, EventArgs e)

{

}

CommonControls.js

/*Commonly Used Functions*/

/*Created By : Ananda Thirumurugan.V */

/*Date : 15_JUNE_2007 */

var arrElements = new Array();

function callGrabFunction(tableID,hdnArray)

{

}

function getValuesInACell(cell) {

for(var i=0;i

var childNode = cell.childNodes[i];

getValuesOfAControl(childNode);

}

function getValuesOfAControl(control) {

if(control.type == "select-one") {

control.selectedIndex=0;

control.disabled=false;

}

else if(control.type == "text") {

alert(control.value);

//control.value = "";

//control.disabled=false;

//if(control.getAttribute("defaultRead")) {

// if(control.getAttribute("defaultRead") == 1)

// control.readOnly=true;

//}

}

else if(control.type == "textarea") {

control.value = "";

control.disabled=false;

}

else if(control.type == "checkbox") {

control.checked = false;

control.disabled=false;

}

else if(control.type == "select-multiple") {

for(var j=childNode.options.length-1;j>0;j--) {

if(control.options[j].selected == true)

control.options[j].selected == false;

//childNode.remove(j);

}

control.disabled=false;

}

//In

//function used to addrow in a table(Table id)

function addRowInATable(tableID) {

var tableObj = getId(tableID);

var rowObj = tableObj.insertRow(tableObj.rows.length);

addCellInARow(tableObj, rowObj);

assignRowClass(tableObj);

}

//function to add specific number of rows

function addSpecificRows(tblID, count) {

for(var i=0;i

addRowInATable(tblID);

//addRowInATable(tblID);

}

//In

//function adds a cell in a row(Table & row object)

function addCellInARow(tableObj, rowObj) {

for(var i=0; i

var cellObj = rowObj.insertCell(i);

cellObj.innerHTML = tableObj.rows[1].cells[i].innerHTML;

// alert(tableObj.rows[i].cells[0].innerHTML)

// alert(tableObj.rows[i].cells[i].innerHTML)

clearValuesInACell(cellObj);

}

//function calls corresponding function based on the control type

function correspondingClearCall(control) {

var type=returnControlType(control);

//alert(control.childNodes[0].tagName);

if(type=="DIV"){

}

else if(type="TABLE") {

dsarClearValuesInATable(control);

}

else if(type=="TR") {

dsarClearValuesInARow(control);

}

else if(type=="TD") {

clearValuesInACell(control);

}

else if(type.match(/INPUT|SELECT|TEXTAREA/gi)) {

clearValuesInAChildNode(control);

}

function returnControlType(control) {

return control.tagName;

}

/*//function

function clearValuesInADiv() {

var length = arguments.length;

for(var i=0;i

clearValuesInATable();

}

}*/

//In

//function clears value of a cell (function will not remove dropdown options)(cell).

function clearValuesInACell(cell) {

for(var i=0;i

var childNode = cell.childNodes[i];

clearValuesOfAControl(childNode);

}

//In

// function clears values of a control and also enables them

function clearValuesOfAControl(control) {

if(control.type == "select-one") {

control.selectedIndex=0;

control.disabled=false;

}

else if(control.type == "text") {

control.value = "";

control.disabled=false;

if(control.getAttribute("defaultRead")) {

if(control.getAttribute("defaultRead") == 1)

control.readOnly=true;

}

else if(control.type == "textarea") {

control.value = "";

control.disabled=false;

}

else if(control.type == "checkbox") {

control.checked = false;

control.disabled=false;

}

else if(control.type == "select-multiple") {

for(var j=childNode.options.length-1;j>0;j--) {

if(control.options[j].selected == true)

control.options[j].selected == false;

//childNode.remove(j);

}

control.disabled=false;

}

// function deletes a row in a table. Expects a table id as a parameter

function deleteRowInATable(tableId) {

var tableObj = getId(tableId)

for(var i=tableObj.rows.length-1;i>=1;i--) {

var length = tableObj.rows[i].cells[tableObj.rows[i].cells.length-1].childNodes.length;

for(var j=0;j

if(tableObj.rows[i].cells[tableObj.rows[i].cells.length-1].childNodes[j].type=="checkbox") {

if(tableObj.rows[i].cells[tableObj.rows[i].cells.length-1].childNodes[j].checked==true) {

var childNode=tableObj.rows[i].cells[tableObj.rows[i].cells.length-1].childNodes[j];

j=length;

deleteRowByControl(childNode);

}

//In

//function deletes the row containing the control.(control object)

function deleteRowByControl(control) {

var row=control.parentNode.parentNode;

var tableObj=row.parentNode;

if(row.rowIndex != 1) {

row.parentNode.deleteRow(row.rowIndex);

assignRowClass(tableObj);}

else {

alert("* This row cannot be deleted.");

control.checked=false;

return false;}

}

//In

//function applies alternating class to the rows in a table.(Table Object)

function assignRowClass(tableObj) {

for(var i=1;i

var rowObj = tableObj.rows[i];

if(rowObj.rowIndex%2==0)

rowObj.className="tablecontent2";

else

rowObj.className="tablecontent1";

}

//function returns necessary validation parameters

function returnValidationParameters(controlID) {

return controlID.valid.split("_");

}

//function validates only mandatory controls

function validateMandatoryControls(childNode) {

if((childNode.type == "text")||(childNode.type == "textarea")) {

if(trim(childNode.value)=="") {

alert(returnAlertMessage(childNode)+childNode.errname);

childNode.focus();

return false;}}

if(childNode.type == "select-one") {

if(trim(childNode.value)=="") {

alert(returnAlertMessage(childNode)+childNode.errname);

childNode.focus();

return false;}}

if(childNode.type == "select-multiple") {

if(!validateMutipleDropdown(childNode)) {

alert(returnAlertMessage(childNode)+childNode.errname);

childNode.focus();

return false;}}

return true;

}

//function returns true if any multiple dropdown option is selected (except Select)

function validateMutipleDropdown(control) {

for(var i=0;i

if(control.options[i].selected == true) {

if((control.options[i].value != "")||(control.options[i].value != "0"))

return true;}

}

return false;

}

//function enables divs(multiple, give as comma seperated(no ' or ""))//

function DSAREnableDivs() {

var length = arguments.length;

for(var i=0;i

arguments[i].style.display="block";}

}

//function disables divs(multiple, give as comma seperated(no ' or ""))//

function DSARDisableDivs() {

var length = arguments.length;

for(var i=0;i

arguments[i].style.display="none";}

}

//function removes spaces and returns the string

function trim(str) {

return str.toString().replace(/(^\s*|\s*$)/gi,"");

}

function showPopupPage(url) {

window.open(url,"","height=400,width=600,toolbar=no,minimize=no,status=no,memubar=no,location=no, scrollbars=yes");

}

//function returns object of any element / control, given the id.

function getId(controlID) {

return document.getElementById(controlID);

}

/*Commonly Used Functions*/

Default2.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default2.aspx.cs" Inherits="Default2" %>

<%@ Register Assembly="System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"

Namespace="System.Web.UI" TagPrefix="asp" %>

<%@ Register Src="AddMore.ascx" TagName="AddMore" TagPrefix="uc1" %>

DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<title>Custom Controlstitle>

head>

<body>

<asp:ScriptManager ID="ScriptManager1" runat="server">

asp:ScriptManager>

<asp:UpdatePanel ID="UpdatePanel1" runat="server">

<div>

<tr>

<td>

Add and delete demo:

td>

tr>

<tr>

<td>

td>

<td>

td>

<td>

td>

<td>

td>

tr>

<uc1:AddMore ID="AddMore1" runat="server" />

table>

div>

ContentTemplate>

asp:UpdatePanel>

<input class="button" id="btnGets" type="button" value="Get Valuess" runat="server"

onclick="javascript:getAllValues('tblAddMorea')" />

form>

body>

html>

Default2.aspx.cs

using System;

using System.Data;

using System.Configuration;

using System.Collections;

using System.Web;

using System.Web.Security;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Web.UI.WebControls.WebParts;

using System.Web.UI.HtmlControls;

using System.Runtime.InteropServices;

public partial class Default2 : System.Web.UI.Page

{

[DllImport("user32.dll", CharSet = CharSet.Unicode)]

public static extern int MessageBox(IntPtr hWnd,String Text,String Caption,uint type);

protected void Page_Load(object sender, EventArgs e)

{

//MessageBox(new IntPtr(0), "Hello World", "Hello Dialog", 0);

}

Happy Coding!!!!

Runtime Hosts

2008-10-17T04:14:00.001-07:00

The common language runtime has been designed to support a variety of different types of applications, from Web server applications to applications with a traditional rich Windows user interface. Each type of application requires a runtime host to start it. The runtime host loads the runtime into a process, creates the application domains within the process, and loads user code into the application domains.

The .NET Framework ships with a number of different runtime hosts, including the hosts listed in the following table.

Runtime Host	Description
ASP.NET	Loads the runtime into the process that is to handle the Web request. ASP.NET also creates an application domain for each Web application that will run on a Web server.
Microsoft Internet Explorer	Creates application domains in which to run managed controls. The .NET Framework supports the download and execution of browser-based controls. The runtime interfaces with the extensibility mechanism of Microsoft Internet Explorer through a mime filter to create application domains in which to run the managed controls. By default, one application domain is created for each Web site.
Shell executables	Invokes runtime hosting code to transfer control to the runtime each time an executable is launched from the shell.

Microsoft provides a set of APIs for writing your own runtime hosts.

A runtime host is defined as any process that loads the .NET runtime and runs code in a managed environment. The most common scenario is that a runtime host is simply a bootstrap program that executes from the Windows shell, loads the runtime into memory, and then loads one or more managed assemblies. An assembly is the unit of deployment in .NET roughly analogous to an executable program or DLL in prior versions of Windows.

A runtime host loads the runtime by using the ICorRuntimeHost or CorBindToRuntimeEx, prior to Whidbey. These APIs call a shim DLL, MSCOREE.DLL, whose only job is to load the runtime. Only a single copy of the runtime (also known as the CLR) engine can ever be loaded into a process during the process's lifetime; it is not possible to run multiple versions of the CLR within the same host. In pre-Whidbey versions of .NET, a host could specify only a limited number of parameters to ICorRuntime Host or CorBindToRuntimeEx, namely the following:

· Server or workstation behavior

· Version of the CLR (for example, version 1.0.3705.0)

· Garbage collection behavior

· Whether or not to share Just-In-Time compiled code across AppDomains (an AppDomain is a subdivision of the CLR runtime space)

Two examples of specialized runtime hosts are the ASP.NET worker process and Internet Explorer. The ASP.NET worker process differs in code location and how the executable code, threads, and AppDomains are organized. (We'll discuss AppDomains in the next section.) The ASP.NET worker process divides code into separate "applications," application being a term that is borrowed from Internet Information Server to denote code running in a virtual directory. Code is located in virtual directories, which are mapped to physical directories in the IIS metabase. Internet Explorer is another runtime host with behaviors that differ from the ASP.NET worker or SQL Server 2005. IE loads code when it encounters a specific type of <object> tag in a Web page. The location of the code is obtained from an HTML attribute of the tag. SQL Server 2005 is an example of a specialized runtime host that goes far beyond ASP.NET in specialization and control of CLR semantics.

http://www.west-wind.com/presentations/aspnetruntime/aspnetruntime.asp

Reference counting:

2008-10-16T23:18:00.001-07:00

In computer science, reference counting is a technique of storing the number of references, pointers, or handles to a resource such as an object or block of memory. It is typically used as a means of de allocating objects which are no longer referenced.

Reference counting is often known as a garbage collection algorithm where each object contains a count of the number of references to it held by other objects. If an object's reference count reaches zero, the object has become inaccessible, and it is put on a list of objects to be destroyed.

Simple reference counts require frequent updates. Whenever a reference is destroyed or overwritten, the reference count of the object it references is decremented, and whenever one is created or copied, the reference count of the object it references is incremented.

Reference counting is also used in disk operating systems and distributed systems, where full non-incremental tracing garbage collection is too time consuming because of the size of the object graph and slow access speed.

COM developers are accustomed to implementing reference counting as a manual memory management technique. Each time an object is referenced, a counter is incremented. When a reference to an object goes out of scope, the counter is decremented. When an object's reference count reaches zero, the object is terminated and its memory is freed.

The reference counting scheme is the source of many bugs. If the reference counting rules are not followed precisely, objects might be freed prematurely or unreferenced objects might accumulate in memory. Circular references are also a common source of bugs. A circular reference occurs when a child object has a reference to a parent object, and the parent object has a reference to the child object. This scenario prevents either object from being released or destroyed. The only solution is for the parent and child objects to agree on a fixed pattern of usage and destruction, such as where the parent always deletes the child first.

When you develop applications in a language that targets the common language runtime, the runtime's garbage collector eliminates the need for reference counting and, as a result, the bugs that can arise from this manual memory management scheme.

Advantages and Disadvantages

References:

http://en.wikipedia.org/wiki/Reference_counting

http://www.brpreiss.com/books/opus5/html/page421.html

To display the message box in asp.net

2008-10-16T01:41:00.001-07:00

Use the namespace

using System.Runtime.InteropServices;

Then use DllImport

"DllImportAttribute Class Indicates that the attributed method is exposed by an unmanaged dynamic-link library (DLL) as a static entry point."

Use the lines below

[DllImport("user32.dll", CharSet = CharSet.Unicode)]

public static extern int MessageBox(IntPtr hWnd,String Text,String Caption,uint type);

InPtr This type implements the ISerializable interface.

And then put this code

MessageBox(new IntPtr(0), "Hello World", "Hello Dialog name", 0);

Note:

The DllImportAttribute does not support marshaling of generic types.

To get the row number in SQL2000.

2008-10-15T05:26:00.001-07:00

SELECT *,(SELECT COUNT(*) FROM Mas_Company

e2 WHERE e2.Company_Code <= e.Company_Code) AS 'rownumber', Mas_Company.*, Company_Code AS Expr1, Company_Name AS Expr2, Company_SName AS Expr3, Company_Add1 AS Expr4,

Company_Add2 AS Expr5, Company_City AS Expr6, Company_Pincode AS Expr7, Company_ph_no AS Expr8, Company_Active_Flag AS Expr9

FROM Mas_Company e

To Avoid the session end showing up the yellow page

2008-09-15T04:23:00.001-07:00

try
{
if (Session["USER"] != null)
{
_PKID = Convert.ToInt32(hshTableSession["UserPKID"]);
}
else { _PKID = 0; }
}
catch { Response.Redirect("LoginPage.aspx"); }

Grid View CSS

2008-07-31T02:34:00.001-07:00

The css for the grid view

.grdFrame
{
border-style:solid;
border-color:#BDCAD0;
border-width:1px;
}

.grdHeaderStyle
{
font-family:"Trebuchet MS";
font-size:9pt;
font-weight:bold;
color:#015aad;
text-decoration:none;
background-color:#cfdfe9;
border-bottom-style:solid;
border-bottom-color:#BDCAD0;
border-bottom-width:1px;
height: 25px;
padding-left:5px;
text-align: left;
}

.grdRowStyle
{
font-family:Helvetica;
font-size:9pt;
color:#191A1C;
font-weight:400;
display:block;
text-decoration:none;
background-color:#FFFFFF;
border-bottom-style:solid;
border-bottom-color:#BDCAD0;
border-bottom-width:1px;
padding-left: 5px;
padding-right: 5px;
text-align:left;
height: 30px;
text-align:left;
}

.grdAltRowStyle
{
font-family:Helvetica;
font-size:9pt;
font-weight:400;
display:block;
color:#191A1C;
text-decoration:none;
background-color:#ebf4f7;
border-bottom-style:solid;
border-bottom-color:#BDCAD0;
border-bottom-width:1px;
padding-left: 5px;
text-align:left;
height: 20px;
}

A New search engine

2008-07-29T03:16:00.001-07:00

A New search engine

http://www.cuil.com/

claims that it's searching 121,617,892,992 web pages

Sad end (Or Beginning) ?

http://www.webpronews.com/topnews/2008/07/28/cuil-crashes-and-burns-at-launch

Google Counts More Than 1 Trillion Unique Web URLs

2008-07-28T03:37:00.001-07:00

http://www.cio.com/article/print/439495

10 ASP.NET Performance and Scalability Secrets

2008-07-23T04:36:00.001-07:00

http://msmvps.com/blogs/omar/archive/2008/01/30/10-asp-net-performance-and-scalability-secrets.aspx

Fast, Streaming AJAX proxy - continuously download from cross domain

2008-04-30T00:06:00.001-07:00

Due to browser's prohibition on cross domain XMLHTTP call, all AJAX websites must have server side proxy to fetch content from external domain like Flickr or Digg. From client side javascript code, an XMLHTTP call goes to the server side proxy hosted on the same domain and then the proxy downloads the content from the external server and sends back to the browser. In general, all AJAX websites on the Internet that are showing content from external domains are following this proxy approach except some rare ones who are using JSONP. Such a proxy gets a very large number of hits when a lot of component on the website are downloading content from external domains. So, it becomes a scalability issue when the proxy starts getting millions of hits. Moreover, web page's overall load performance largely depends on the performance of the proxy as it delivers content to the page. In this article, we will take a look how we can take a conventional AJAX Proxy and make it faster, asynchronous .....................for full article read http://msmvps.com/blogs/omar/archive/2008/04/14/fast-streaming-ajax-proxy-continuously-download-from-cross-domain.aspx

Author's address

http://msmvps.com/blogs/omar/archive/2008/04/14/fast-streaming-ajax-proxy-continuously-download-from-cross-domain.aspx

Blogger's address

http://www.thirusystems.com/

Serviced Component

2008-04-23T04:03:00.000-07:00

A serviced component is the mechanism that enables COM+ services to be available to .NET Framework classes. This section describes how to configure and register serviced components for access to COM+ services.

Just-in-Time (JIT) Activation, Synchronization, Object Pooling, Transactions, and Shared Property Management are examples of well-known COM+ services that are available for you to use. There are also other COM+ services, such as loosely coupled events, Queued Components, and role-based security that you can use to write flexible, Web-based applications.

Note You can modify any Common Language Specification (CLS)–compliant class to use COM+ services. The System.EnterpriseServices namespace provides custom attributes and classes for accessing these services from managed code.

Detailed Reading:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconwritingservicedcomponents.asp

Owners site : http://www.thirusystems.com/

Blog: http://codecenter.blogspot.com

Computer Hangs After 49.7 Days in Windows OS

2008-04-04T01:39:00.001-07:00

Will Windows work continuously for more than 49.7 days?

Here is a bit of information, which may surprise you all. Windows
crashes automatically if you don't switch off the machine for 49.7 Days.
Microsoft accepts this. Do you know why?

In Windows the Virtual Machine Manager (here after referred as VMM) is
responsible for creation, execution, monitoring and termination of
virtual machines. This VMM, which is a 32 bit, protected mode operating
system entity, provides a number of system services at chip level. One
of these services is "Get_System_Time". This particular service loads
the EAX register with the time in milliseconds since Windows started on
that machine. This service is accurate to 1 ms. EAX is a 32 bit register
in Intel 386 Processor onwards.

So the maximum number of milliseconds it can hold is
(232)-1 = 4294967295 milliseconds = 4294967.295 seconds = 71582.79
minutes = 1193 hours = 49.7 days.

So after 49.7 days the EAX resets to zero. Most of the Drivers use this
Time Service to keep track of the Timeout of various services they
provide. So after 49.7 days the drivers cannot use the Get_System_Time
function of VMM and they crash taking the OS along with.

Please check this knowledge base article 216641:
http://support.microsoft.com/kb/216641/EN-US/

"Kumar @ Vimal S" <skumarstech@gmail.com>,

How to Fix Double Click Always Opens Search in Windows Explorer

2008-03-26T23:17:00.001-07:00

If you mess around in the registry, or install some different software packages that add things to the right-click menu, you can end up with a problem where the default action on a folder is always "Search…", even though you set it to something else.

There's a quick and easy fix for this problem. Open up regedit.exe by using Start\Run and then browse down to this registry key:

HKEY_CLASSES_ROOT\Directory\shell

Double-click on the default value and set it to "none" without the quotes, as seen here:

This will restore the normal behavior.

Update

If you are also experiencing this problem when you try to click on a drive, you can run this command from the run box or command prompt:

regsvr32 /i shell32.dll

This should restore the normal behavior.

If you are getting a message that says "Windows cannot find 'PET32.exe'", then at some point you had a virus, or still have a virus. First, make sure that you run a virus scanner to get rid of the virus. Then run the regsvr32 command above, which should fix the problem.

http://www.thirusystems.com/

http://codecenter.blogspot.com

.NET Framework 3.0

2008-03-04T06:29:00.000-08:00

.NET Framework 3.0 new features

.NET Framework 3.0, formerly called WinFX, includes a new set of managed code APIs that are an integral part of Windows Vista and Windows Server 2008 operating systems. It is also available for Windows XP SP2 and Windows Server 2003 as a download. There are no major architectural changes included with this release; .NET Framework 3.0 uses the Common Language Runtime of .NET Framework 2.0.[13] Unlike the previous major .NET releases, there was no .NET Compact Framework release made as a counterpart of this version.

.NET Framework 3.0 consists of four major new components:

* Windows Presentation Foundation (WPF), formerly code-named Avalon; a new user interface subsystem and API based on XML and vector graphics, which uses 3D computer graphics hardware and Direct3D technologies. See WPF SDK for developer articles and documentation on WPF.
* Windows Communication Foundation (WCF), formerly code-named Indigo; a service-oriented messaging system which allows programs to interoperate locally or remotely similar to web services.
* Windows Workflow Foundation (WF) allows for building of task automation and integrated transactions using workflows.
* Windows CardSpace, formerly code-named InfoCard; a software component which securely stores a person's digital identities and provides a unified interface for choosing the identity for a particular transaction, such as logging in to a website.

Windows Presentation Foundation (WPF)

http://en.wikipedia.org/wiki/Windows_Presentation_Foundation

Windows Communication Foundation (WCF)

http://en.wikipedia.org/wiki/Windows_Communication_Foundation

Windows Workflow Foundation (WF)

http://en.wikipedia.org/wiki/Windows_Workflow_Foundation

Windows CardSpace

http://en.wikipedia.org/wiki/Windows_CardSpace

New features of Visual Studio 2008

2008-02-26T21:43:00.000-08:00

New features of Visual Studio 2008

The following are important new features that are part of new Visual Studio 2008.

Settings Migration:

If you have Visual Studio 2005 and Visual Studio 2008 installed on the same computer, then when you first start Visual Studio 2008, you can migrate most of your settings from Visual Studio 2005.

Community and Help Menus:

The Community menu has been removed for Visual Studio 2008. The commands formerly known as Ask a Question and Check Question Status have been combined into a new command named MSDN Forums, which is on the Help menu.

General User Elements:

Several user interface (UI) elements have been updated. These include the following:

IDE Navigator: An improved interface makes switching between items easier.
Common dialog boxes: Visual Studio 2008 uses Windows standard dialog boxes instead of custom dialog boxes. This makes the navigation experience more consistent with that of Windows.
You can now specify a custom font for IDE elements not identified individually in the Show settings for list in the Fonts and Colors, Environment, Options Dialog Box by using the new option Environment Font.

Web Application Projects:

The new Web application project model provides the same Web project semantics as the Visual Studio .NET 2003 Web project model. This includes a structure based on project files and a build model based on compiling all the code for a project into a single assembly.

Other changes:

FrontPage Server Extensions are no longer required.

Internet Information Services is no longer mandatory. Support for both IIS and the built-in ASP.NET Development Server is included.

AJAX Development:

The AJAX server-based and client-based programming models are supported by the following:

Server controls that support server-based AJAX development. This includes the ScriptManager, UpdatePanel, UpdateProgress, and Timer controls.
The Microsoft AJAX Library, which supports client-based, object-oriented development.
Server classes that enable you to develop server controls that map to custom client components whose events and properties are set declaratively.
Support for script globalization and localization.

Support for Windows Presentation Foundation (WPF) Applications:

Windows Presentation Foundation (WPF) applications have been added to Visual Studio 2008. There are four WPF project types:

WPF Application (.xaml, .exe)
WPF Browser Application (.exe, .xbap)
WPF Custom Control Library (.dll)
WPF User Control Library (.dll)

Support for Web Application Projects:

Web Application projects were included in Visual Studio 2008. The new Web Application project model provides the same Web Application project semantics as the Visual Studio .NET 2003 Web project model.

Multitargeting Support:

Multitargeting lets you target code to a specific .NET Framework version:

.NET Framework 2.0, which was included with Visual Studio 2005.
.NET Framework 3.0, which is included with Windows Vista.
.NET Framework 3.5, which is included with Visual Studio 2008.

Enhanced ClickOnce Deployment:

ClickOnce deployment has the following new features:

ClickOnce supports the deployment of WPF Web Browser Applications.
ClickOnce gives ISVs the option to re-sign the application manifest with their customer's company name, application name, and deployment/support URL.
You can build and deploy Visual Studio Tools for Office applications by using the Project Designer's Publish page or the Publish Wizard.
ClickOnce supports manifest generation under User Access Control (UAC) on Windows Vista.

Updated Windows Installer Deployment:

Windows Installer deployment has been updated for:

Installation on Windows Vista is smooth.
Supports applications which are targeting new .NET Framework 3.0 and 3.5 versions.

CSS Design Tools:

Working with cascading style sheets (CSS) is enhanced in Visual Studio 2008 and easier than ever. Much of the work designing the layout and styling content can be done in Design view using the CSS Properties grid, the Apply Styles and Manage Styles panes, and the Direct Style Application tool.

Improved IntelliSense:

IntelliSense has been improved and now supports JScript authoring and ASP.NET AJAX scripting. Client script that is included in a Web page by using tags now has the benefit of IntelliSense, as do .js script files.

Integrated WPF Designer:

The WPF Designer combines real-time editing of XAML with an enhanced graphical design-time experience. The following features are new for the WPF Designer:

SplitView lets you adjust objects in the graphical designer and immediately view the changes to the underlying XAML code.
The Document Outline window lets you view and move through your XAML with full selection synchronization between the designer, the document outline, the XAML editor, and the Properties window.
IntelliSense in the XAML editor enables rapid code entry.
Grid lines can be added to grids in the designer to enable easy grid-based control placement.
Snap lines let you easily align controls and text.
Design-time extensibility supports design mode and property editors.

Data:

The Object Relational Designer provided for creating and editing the LINQ to SQL objects that map between an application and a database.
N-Tier support for typed datasets provides enhancements to the Dataset Designer that assist in separating TableAdapter code and typed dataset code into discrete projects.
Hierarchical update capabilities have been incorporated into the Dataset Designer to enable saving data in multiple related tables.
Local database caching incorporates a SQL Server Compact 3.5 database and Microsoft Synchronization Services for ADO.NET into an application and prepares the application to periodically synchronize the data with a remote database on a server.
Microsoft SQL Server Compact 3.5 is a compact database that can be deployed on desktop computers, smart devices, and Tablet PCs.

Language-Integrated Query (LINQ):

Language-Integrated Query (LINQ) is a new set of features in Visual Studio 2008 that extend powerful query capabilities into the language syntax of C# and Visual Basic. Visual Studio 2008 includes LINQ provider assemblies that enable language-integrated querying of .NET Framework collections (LINQ to Objects), SQL Databases (LINQ to SQL), ADO.NET Datasets (LINQ to ADO.NET), and XML documents (LINQ to XML).

Client Application Services:

Client application services are new in the .NET Framework 3.5 and enable Windows-based applications to easily access the ASP.NET login, roles, and profile services. These services let you authenticate users and retrieve user roles and application settings from a shared server.

New Report Projects:

Visual Studio 2008 includes two new project templates for creating reporting applications.

Report Wizard:

Visual Studio 2008 introduces a Report Wizard, which guides you through the steps to create a basic report.

Expression Editor Enhancement:

The Expression Editor now provides sample expressions that you can use in report expressions.

ReportViewer Printing:

The RSClientPrint control is now available when the ASP.NET ReportViewer control is configured for local processing.

PDF Compression:

The ReportViewer controls will now compress reports that are rendered or exported to the PDF format when they are configured for local processing.

Multiple Processor Capabilities:

MSBuild now recognizes when a system is using multiple processors, either multicore processors or multiple separate processors.

Enhanced Logging:

Build event logging has been upgraded to handle multi-processor builds.

Technical References:

http://msdn.microsoft.com

New features in SQL Server 2008

2008-02-22T00:45:00.000-08:00

New features in SQL Server 2008

In SQL Server 2008, improvements are made to core database engine, Analysis Services, Integration Services, Replication, Reporting Services and Service broker. These features are based on the October, 2007 CTP; the final product may have variations to these features.

Database Engine Improvements

Backup Compression:

This is introduced in Enterprise or above editions. Now sql server supports compressing backups. Compressed backup can be restored to any edition of sql server 2008.

Configuration Servers:

This is a new method of administering multiple servers. An instance of sql server is designated as a configuration server to maintain list of registered servers.

Change Tracking:

SQL Server now allows applications to obtain incremental changes to user tables by tracking changes, which enables developing synchronization applications is easier and faster.

FILESTREAM storage:

FILESTREAM in SQL Server 2008 enables SQL Server-based applications to store unstructured data, such as documents and images, on the file system. FILESTREAM integrates the SQL Server Database Engine with an NTFS file system by storing varbinary(max) binary large object (BLOB) data as files on the file system. Transact-SQL statements can insert, update, query, search, and back up FILESTREAM data.

Hot Add CPU:

SQL Server 2008 supports dynamically adding CPUs to a running system. Adding CPUs can occur physically by adding new hardware, logically by online hardware partitioning, or virtually through a virtualization layer.

Plan Guide Enhancements:

The sp_create_plan_guide stored procedure has been extended to accept XML Showplan output directly in the @hints parameter instead of embedding the output in the USE PLAN hint. This simplifies the process of applying a fixed query plan as a plan guide hint. You can create multiple OBJECT or SQL plan guides for the same query and batch or module. However, only one of these plan guides can be enabled at any given time.

Query Processing on Partitioned Objects:

SQL Server 2008 improves query processing performance on partitioned tables for many parallel plans, changes the way parallel and serial plans are represented, and enhances the partitioning information provided in both compile-time and run-time execution plans.

Partition Switching on Partitioned Tables and Indexes:

Partitioning data enables you to manage and access subsets of your data quickly and efficiently while maintaining the integrity of the entire data collection. Now you can use partition switching to quickly and efficiently transfer subsets of your data by switching a partition from one table to another.

Resource Governor:

Resource Governor is a feature that you can use to manage SQL Server workload and system resource consumption. Resource Governor enables you to limit the amount of CPU and memory that incoming application requests can use.

Extensible Key Management:

The Extensible Key Management (EKM) feature in the Enterprise, Developer, and Evaluation Editions of SQL Server 2008 allows third-party enterprise key management and hardware security module (HSM) vendors to register their devices in SQL Server.

Transparent Data Encryption:

Transparent Data Encryption introduces a new database option that encrypts the database files automatically, without needing to alter any applications.

Server Administration:

SQL Server 2008 introduces Declarative Management, a new policy-based management framework for the SQL Server Database Engine.

Spatial Data Storage, Methods and Indexing:

Spatial data represents information about the physical location and shape of geometric objects. These objects can be point locations or more complex objects such as countries, roads, or lakes.

SQL Server Management Studio Enhancements:

Transact-SQL Query Editor IntelliSense:

The Transact-SQL Editor now provides IntelliSense functionality such as word completion and error underlining. IntelliSense is provided for frequently used Transact-SQL elements.

Transact-SQL Error List Window:

SQL Server Management Studio includes an Error List window that displays the syntax and semantic errors generated from the IntelliSense code in the Transact-SQL Query Editor.

Tools Enhancements:

SQL Server Management Studio has the following improvements:

® In the Query Editor window, you can query multiple servers at the same time by opening query windows from registered server groups. The query results can be combined into a single results pane, or can be returned in separate results panes.

® You can access SQL Server Profiler from the Query Editor window, from the Query menu, the Query Editor toolbar, or by pressing CTRL+ALT+P.

® You can now open tables by using a Return Top n rows option.

® On the Tools/Option menu, you can specify the action that results by double-clicking tables in Object Explorer.

Transact-SQL Enhancements:

Lock Escalation Option - A new LOCK_ESCALATION option of ALTER TABLE allows you to disable lock escalation on a table.

Query Hints - Table hints can now be specified as query hints to provide advanced query performance tuning options.

hierarchyid Data Type - SQL Server 2008 introduces a new system-provided data type to encapsulate hierarchical relationships.

MERGE Statement - This new Transact-SQL statement performs INSERT, UPDATE, or DELETE operations on a target table based on the results of a join with a source table.

Table-Valued Parameters - The Database Engine introduces a new parameter type that can reference user-defined table types.

User-Defined Table Type - The Database Engine introduces a new user-defined table type that supports representing table structures for use as parameters in stored procedures and functions, or in a batch or the body of a stored procedure or function.

Compatibility Level - ALTER DATABASE SET COMPATIBILITY_LEVEL replaces sp_dbcmptlevel for setting the database compatibility level.

GROUPING SETS - The GROUPING SETS, ROLLUP, and CUBE operators are added to the GROUP BY clause.

Table Hints - The FORCESEEK table hint is added to provide advanced query performance tuning options.

Transact-SQL Row Constructors - Transact-SQL is enhanced to allow multiple value inserts within a single INSERT statement.

Data Collector:

SQL Server 2008 introduces a data collector that you can use to obtain and save data that is gathered from several sources.

Database Mirroring:

Log Performance Enhancements:

® Compression of stream data for which at least a 12.5 percent compression ratio can be achieved.

® Write-ahead on the incoming log stream on the mirror server.

® Improved use of log send buffers.

® Page read-ahead during the undo phase.

Automatic Recovery from Corrupted Pages:

A database mirroring partner running on SQL Server 2008 or later versions automatically tries to resolve certain types of errors that prevent reading a data page.

SQL Dependency Reporting Enhancements:

SQL Server 2008 introduces a new catalog view and system functions to provide consistent and reliable SQL dependency reporting.

SQL Server Extended Events:

SQL Server 2008 introduces SQL Server Extended Events, an event infrastructure for server systems.

Change Data Capture:

Change data capture is designed to capture insert, update, and delete activity applied to SQL Server tables, and to make the details of the changes available in an easily consumed relational format.

Optimized Bitmap Filtering:

The query optimizer can place bitmap filters dynamically in parallel query plans to improve the performance of queries against a star schema.

Dynamic Management Views:

There are five new dynamic management views to present memory information.

DDL Triggers and Event Notifications:

The class of events on which you can create DDL triggers and event notifications is expanded to include numerous stored procedures that perform DDL-like operations.

For more info visit:

http://www.microsoft.com/sql/2008/default.mspx

http://geekswithblogs.net/Sreeblog/articles/117576.aspx

Top 10 Reasons to Switch from Java to Visual C#

2006-10-18T00:03:00.000-07:00

Top 10 Reasons to Switch from Java to Visual C#
By Will Wagers

"Prepare to be assimilated.... Resistance is futile."
- Borg, "Q, Who?", Startrek: The Next Generation

Why should a Java developer switch to C#? Here are the major reasons in alphabetical order:

1. "C Style" memory access
Rather than forcing developers to write code to access application programming interfaces (APIs) in other languages in order to access specific memory locations ( e.g. hardware-mapped memory), C# allows developers to use "C style" memory management and pointers when necessary. Of course, one of the major design goals of the Java language and other object-oriented languages is specifically to outlaw such access. A fact which Microsoft acknowledges by forcing the C# programmer to label such accesses with the unsafe keyword.

2. Extensions for component-oriented development
Visual C# provides developers with a powerful component-oriented development language that includes support for properties, indexers, delegates, inheritance, versioning, and attributes, without the need for esoteric or rigid naming patterns and companion classes.

3. Familiarity
Java developers will immediately find Visual C# to be familiar and comfortable. C# is like Java on steroids. There are some extra keywords; and, Visual C# supports some extra constructs. But, a Java coder can learn the C# language in a day or two. Learning the APIs is a different matter.

4. Interactive XML Web services
Visual C# allows developers to deploy and consume rich, interactive XML Web services that reduce development time by enabling software aggregation from any platform. Microsoft is famous for hiding the details from the developer: This is both good and bad. New developers may not actually know or understand what is going on under the hood. On the other hand, it does increase productivity. Of course, Java developers have a variety of IDEs such as Eclipse to choose from. All of which provide some degree of support for Web services.

5. Leverage the .NET Framework
Visual C# provides developers with access to the Microsoft .NET Framework--a robust, thread-safe library of collection classes, data access classes, networking functions, etc. Recently, however, various bridge software offer .NET access from Java programs as well as access to the rich Java libraries from .NET languages.

6. Object-based type system
Visual C# provides developers an object-based type system that eliminates the need for complex, verbose data marshalling code commonly required by Java applications.

7. Standards-based language
Visual C# provides developers with a standards-based language (ECMA) with all its advantages. This is a significant advantage over the Java language.

8. Target any device
Visual C# lets developers target desktop computers or a variety of handheld and wireless devices using identical tools and skills. True, but all the devices must be Windows based.

9. Visual Studio .NET IDE
Visual C# provides developers with the Visual Studio .NET integrated development environment (IDE) which includes support for task lists, property editors, Microsoft IntelliSense®, Forms designers, etc. For development on Windows platform, Visual Studio is king. However, Visual Studio lags Eclipse and other IDEs except in Microsoft-specific features.

10. XML comments
Visual C# allows developers to use eXtensible Markup Language (XML) Comments to provide useful and customizable source code documentation. Of course, so does Java although Microsoft does add its own twists to it.

Conclusion
A form of this top 10 list originated with Microsoft. But, because both Java software and Visual C# evolve competitively, non-Microsoft oriented features tend to be matched by each competitor in turn. There is no real reason to use Visual C# instead of Java in general; because, each has its own advantages and disadvantages which may or may not be important in specific situations. Unless you work in a Microsoft-only shop, the requirements of the project should dictate both the language and other software employed.

C# Interview Questions

2006-10-17T23:31:00.000-07:00

C# Interview Questions

General Questions

Does C# support multiple-inheritance?
No.

Who is a protected class-level variable available to?
It is available to any sub-class (a class inheriting this class).

Are private class-level variables inherited?
Yes, but they are not accessible. Although they are not visible or accessible via the class interface, they are inherited.

Describe the accessibility modifier "protected internal".
It is available to classes that are within the same assembly and derived from the specified base class.

What's the top .NET class that everything is derived from?
System.Object.

What does the term immutable mean?
The data value may not be changed. Note: The variable value may be changed, but the original immutable data value was discarded and a new data value was created in memory.

What's the difference between System.String and System.Text.StringBuilder classes?
System.String is immutable. System.StringBuilder was designed with the purpose of having a mutable string where a variety of operations can be performed.

What's the advantage of using System.Text.StringBuilder over System.String?
StringBuilder is more efficient in cases where there is a large amount of string manipulation. Strings are immutable, so each time a string is changed, a new instance in memory is created.

Can you store multiple data types in System.Array?
No.

What's the difference between the System.Array.CopyTo() and System.Array.Clone()?
The Clone() method returns a new array (a shallow copy) object containing all the elements in the original array. The CopyTo() method copies the elements into another existing array. Both perform a shallow copy. A shallow copy means the contents (each array element) contains references to the same object as the elements in the original array. A deep copy (which neither of these methods performs) would create a new instance of each element's object, resulting in a different, yet identacle object.

How can you sort the elements of the array in descending order?
By calling Sort() and then Reverse() methods.

What's the .NET collection class that allows an element to be accessed using a unique key?
HashTable.

What class is underneath the SortedList class?
A sorted HashTable.

Will the finally block get executed if an exception has not occurred?
Yes.

What's the C# syntax to catch any possible exception?
A catch block that catches the exception of type System.Exception. You can also omit the parameter data type in this case and just write catch {}.

Can multiple catch blocks be executed for a single try statement?
No. Once the proper catch block processed, control is transferred to the finally block (if there are any).

Explain the three services model commonly know as a three-tier application.
Presentation (UI), Business (logic and underlying code) and Data (from storage or other sources).

Class Questions

What is the syntax to inherit from a class in C#?
Place a colon and then the name of the base class.
Example: class MyNewClass : MyBaseClass

Can you prevent your class from being inherited by another class?
Yes. The keyword "sealed" will prevent the class from being inherited.

Can you allow a class to be inherited, but prevent the method from being over-ridden?
Yes. Just leave the class public and make the method sealed.

What's an abstract class?
A class that cannot be instantiated. An abstract class is a class that must be inherited and have the methods overridden. An abstract class is essentially a blueprint for a class without any implementation.

When do you absolutely have to declare a class as abstract?
1. When the class itself is inherited from an abstract class, but not all base abstract methods have been overridden.
2. When at least one of the methods in the class is abstract.

What is an interface class?
Interfaces, like classes, define a set of properties, methods, and events. But unlike classes, interfaces do not provide implementation. They are implemented by classes, and defined as separate entities from classes.

Why can't you specify the accessibility modifier for methods inside the interface?
They all must be public, and are therefore public by default.

Can you inherit multiple interfaces?
Yes. .NET does support multiple interfaces.

What happens if you inherit multiple interfaces and they have conflicting method names?
It's up to you to implement the method inside your own class, so implementation is left entirely up to you. This might cause a problem on a higher-level scale if similarly named methods from different interfaces expect different data, but as far as compiler cares you're okay.
To Do: Investigate

What's the difference between an interface and abstract class?
In an interface class, all methods are abstract - there is no implementation. In an abstract class some methods can be concrete. In an interface class, no accessibility modifiers are allowed. An abstract class may have accessibility modifiers.

What is the difference between a Struct and a Class?
Structs are value-type variables and are thus saved on the stack, additional overhead but faster retrieval. Another difference is that structs cannot inherit.

Method and Property Questions

What's the implicit name of the parameter that gets passed into the set method/property of a class?
Value. The data type of the value parameter is defined by whatever data type the property is declared as.

What does the keyword "virtual" declare for a method or property?
The method or property can be overridden.

How is method overriding different from method overloading?
When overriding a method, you change the behavior of the method for the derived class. Overloading a method simply involves having another method with the same name within the class.

Can you declare an override method to be static if the original method is not static?
No. The signature of the virtual method must remain the same. (Note: Only the keyword virtual is changed to keyword override)

What are the different ways a method can be overloaded?
Different parameter data types, different number of parameters, different order of parameters.

If a base class has a number of overloaded constructors, and an inheriting class has a number of overloaded constructors; can you enforce a call from an inherited constructor to a specific base constructor?
Yes, just place a colon, and then keyword base (parameter list to invoke the appropriate constructor) in the overloaded constructor definition inside the inherited class.

Events and Delegates

What's a delegate?
A delegate object encapsulates a reference to a method.

What's a multicast delegate?
A delegate that has multiple handlers assigned to it. Each assigned handler (method) is called.

XML Documentation Questions

Is XML case-sensitive?
Yes.

What's the difference between // comments, /* */ comments and /// comments?
Single-line comments, multi-line comments, and XML documentation comments.

How do you generate documentation from the C# file commented properly with a command-line compiler?
Compile it with the /doc switch.

Debugging and Testing Questions

What debugging tools come with the .NET SDK?
1. CorDBG – command-line debugger. To use CorDbg, you must compile the original C# file using the /debug switch.
2. DbgCLR – graphic debugger. Visual Studio .NET uses the DbgCLR.

What does assert() method do?
In debug compilation, assert takes in a Boolean condition as a parameter, and shows the error dialog if the condition is false. The program proceeds without any interruption if the condition is true.

What's the difference between the Debug class and Trace class?
Documentation looks the same. Use Debug class for debug builds, use Trace class for both debug and release builds.

Why are there five tracing levels in System.Diagnostics.TraceSwitcher?
The tracing dumps can be quite verbose. For applications that are constantly running you run the risk of overloading the machine and the hard drive. Five levels range from None to Verbose, allowing you to fine-tune the tracing activities.

Where is the output of TextWriterTraceListener redirected?
To the Console or a text file depending on the parameter passed to the constructor.

How do you debug an ASP.NET Web application?
Attach the aspnet_wp.exe process to the DbgClr debugger.

What are three test cases you should go through in unit testing?
1. Positive test cases (correct data, correct output).
2. Negative test cases (broken or missing data, proper handling).
3. Exception test cases (exceptions are thrown and caught properly).

Can you change the value of a variable while debugging a C# application?
Yes. If you are debugging via Visual Studio.NET, just go to Immediate window.

ADO.NET and Database Questions

What is the role of the DataReader class in ADO.NET connections?
It returns a read-only, forward-only rowset from the data source. A DataReader provides fast access when a forward-only sequential read is needed.

What are advantages and disadvantages of Microsoft-provided data provider classes in ADO.NET?
SQLServer.NET data provider is high-speed and robust, but requires SQL Server license purchased from Microsoft. OLE-DB.NET is universal for accessing other sources, like Oracle, DB2, Microsoft Access and Informix. OLE-DB.NET is a .NET layer on top of the OLE layer, so it's not as fastest and efficient as SqlServer.NET.

What is the wildcard character in SQL?
Let's say you want to query database with LIKE for all employees whose name starts with La. The wildcard character is %, the proper query with LIKE would involve 'La%'.

Explain ACID rule of thumb for transactions.
A transaction must be:
1. Atomic - it is one unit of work and does not dependent on previous and following transactions.
2. Consistent - data is either committed or roll back, no "in-between" case where something has been updated and something hasn't.
3. Isolated - no transaction sees the intermediate results of the current transaction).
4. Durable - the values persist if the data had been committed even if the system crashes right after.

What connections does Microsoft SQL Server support?
Windows Authentication (via Active Directory) and SQL Server authentication (via Microsoft SQL Server username and password).

Between Windows Authentication and SQL Server Authentication, which one is trusted and which one is untrusted?
Windows Authentication is trusted because the username and password are checked with the Active Directory, the SQL Server authentication is untrusted, since SQL Server is the only verifier participating in the transaction.

What does the Initial Catalog parameter define in the connection string?
The database name to connect to.

What does the Dispose method do with the connection object?
Deletes it from the memory.
To Do: answer better. The current answer is not entirely correct.

What is a pre-requisite for connection pooling?
Multiple processes must agree that they will share the same connection, where every parameter is the same, including the security settings. The connection string must be identical.

Assembly Questions

How is the DLL Hell problem solved in .NET?
Assembly versioning allows the application to specify not only the library it needs to run (which was available under Win32), but also the version of the assembly.

What are the ways to deploy an assembly?
An MSI installer, a CAB archive, and XCOPY command.

What is a satellite assembly?
When you write a multilingual or multi-cultural application in .NET, and want to distribute the core application separately from the localized modules, the localized assemblies that modify the core application are called satellite assemblies.

What namespaces are necessary to create a localized application?
System.Globalization and System.Resources.

What is the smallest unit of execution in .NET?
an Assembly.

When should you call the garbage collector in .NET?
As a good rule, you should not call the garbage collector. However, you could call the garbage collector when you are done using a large object (or set of objects) to force the garbage collector to dispose of those very large objects from memory. However, this is usually not a good practice.

How do you convert a value-type to a reference-type?
Use Boxing.

What happens in memory when you Box and Unbox a value-type?
Boxing converts a value-type to a reference-type, thus storing the object on the heap. Unboxing converts a reference-type to a value-type, thus storing the value on the stack.

Two Tier Software Architectures

2006-09-14T22:56:00.000-07:00

Two Tier Software Architectures

Purpose and Origin

Two tier software architectures were developed in the 1980s from the file server software architecture design. The two tier architecture is intended to improve usability by supporting a forms-based, user-friendly interface. The two tier architecture improves scalability by accommodating up to 100 users (file server architectures only accommodate a dozen users), and improves flexibility by allowing data to be shared, usually within a homogeneous environment [Schussel 96]. The two tier architecture requires minimal operator intervention, and is frequently used in non-complex, non-time critical information processing systems. Detailed readings on two tier architectures can be found in Schussel and Edelstein [Schussel 96, Edelstein 94].

Technical Detail
Two tier architectures consist of three components distributed in two layers: client (requester of services) and server (provider of services). The three components are

User System Interface (such as session, text input, dialog, and display management services)
Processing Management (such as process development, process enactment, process monitoring, and process resource services)
Database Management (such as data and file services)
The two tier design allocates the user system interface exclusively to the client. It places database management on the server and splits the processing management between client and server, creating two layers. Figure 38 depicts the two tier software architecture.

In general, the user system interface client invokes services from the database management server. In many two tier designs, most of the application portion of processing is in the client environment. The database management server usually provides the portion of the processing related to accessing data (often implemented in store procedures). Clients commonly communicate with the server through SQL statements or a call-level interface. It should be noted that connectivity between tiers can be dynamically changed depending upon the user's request for data and services.

As compared to the file server software architecture (that also supports distributed systems), the two tier architecture improves flexibility and scalability by allocating the two tiers over the computer network. The two tier improves usability (compared to the file sever software architecture) because it makes it easier to provide a customized user system interface.

It is possible for a server to function as a client to a different server- in a hierarchical client/server architecture. This is known as a chained two tier architecture design.

Usage Considerations
Two tier software architectures are used extensively in non-time critical information processing where management and operations of the system are not complex. This design is used frequently in decision support systems where the transaction load is light. Two tier software architectures require minimal operator intervention. The two tier architecture works well in relatively homogeneous environments with processing rules (business rules) that do not change very often and when workgroup size is expected to be fewer than 100 users, such as in small businesses.

Maturity
Two tier client/server architectures have been built and fielded since the middle to late 1980s. The design is well known and used throughout industry. Two tier architecture development was enhanced by fourth generation languages.

Costs and Limitations
Scalability. The two tier design will scale-up to service 100 users on a network. It appears that beyond this number of users, the performance capacity is exceeded. This is because the client and server exchange "keep alive" messages continuously, even when no work is being done, thereby saturating the network [Schussel 96].
Implementing business logic in stored procedures can limit scalability because as more application logic is moved to the database management server, the need for processing power grows. Each client uses the server to execute some part of its application code, and this will ultimately reduce the number of users that can be accommodated.

Interoperability. The two tier architecture limits interoperability by using stored procedures to implement complex processing logic (such as managing distributed database integrity) because stored procedures are normally implemented using a commercial database management system's proprietary language. This means that to change or interoperate with more than one type of database management system, applications may need to be rewritten. Moreover, database management system's proprietary languages are generally not as capable as standard programming languages in that they do not provide a robust programming environment with testing and debugging, version control, and library management capabilities.

System administration and configuration. Two tier architectures can be difficult to administer and maintain because when applications reside on the client, every upgrade must be delivered, installed, and tested on each client. The typical lack of uniformity in the client configurations and lack of control over subsequent configuration changes increase administrative workload.

Batch jobs. The two tiered architecture is not effective running batch programs. The client is typically tied up until the batch job finishes, even if the job executes on the server; thus, the batch job and client users are negatively affected [Edelstein 94].

Dependencies
Developing a two tier client/server architecture following an object-oriented methodology would be dependent on the CORBA standards for design implementation. See Common Object Request Broker Architecture.

Alternatives
Possible alternatives for two tier client server architectures are

the three-tier architecture (see Three Tier Software Architectures) if there is a requirement to accommodate greater than 100 users
distributed/collaborative architectures (see Distributed/Collaborative Enterprise Architectures) if there is a requirement to design on an enterprise-wide scale. An enterprise-wide design is comprised of numerous smaller systems or subsystems.
When preparing a two tier architecture for possible migration to an alternative three tier architecture, the following five steps will make the transition less costly and of lower risk [Dickman 95]:

Eliminate application diversity by ensuring a common, cross-hardware library and development tools.
Develop smaller, more comparable service elements, and allow access through clearly-defined interfaces.
Use an Interface Definition Language (IDL) to model service interfaces and build applications using header files generated when compiled.
Place service elements into separate directories or files in the source code.
Increase flexibility in distributed functionality by inserting service elements into Dynamic Linked Libraries (DLLs) so that they do not need to be complied into programs.
Complementary Technologies
Complementary technologies for two tier architectures are CASE (computer-aided software engineering) tools because they facilitate two tier architecture development, and open systems (see COTS and Open Systems-An Overview) because they facilitate developing architectures that improve scalability and flexibility.

Index Categories
This technology is classified under the following categories. Select a category for a list of related topics.
Name of technology
Two Tier Software Architectures

Application category
Client/Server (AP.2.1.2.1)

Quality measures category
Usability (QM.2.3)
Maintainability (QM.3.1)
Scalability (QM.4.3)

Computing reviews category
Distributed Systems (C.2.4)
Software Engineering Design (D.2.10)

References and Information Sources
[Dickman 95] Dickman, A. "Two-Tier Versus Three-Tier Apps." Informationweek 553 (November 13, 1995): 74-80.
[Edelstein 94] Edelstein, Herb. "Unraveling Client/Server Architecture." DBMS 7, 5 (May 1994): 34(7).
[Gallaugher 96] Gallaugher, J. & Ramanathan, S. "Choosing a Client/Server Architecture. A Comparison of Two-Tier and Three-Tier Systems." Information Systems Management Magazine 13, 2 (Spring 1996): 7-13.
[Louis 95] Louis [online]. Available WWW
(1995).
[Newell 95] Newell, D.; Jones, O.; & Machura, M. "Interoperable Object Models for Large Scale Distributed Systems," 30-31. Proceedings. International Seminar on Client/Server Computing. La Hulpe, Belgium, October 30-31, 1995. London, England: IEE, 1995.
[Schussel 96] Schussel, George. Client/Server Past, Present, and Future [online]. Available WWW
(1995).

Current Author/Maintainer
Darleen Sadoski, GTE

Ref : http://www.sei.cmu.edu/str/descriptions/twotier_body.html

Denial-of-service attack

2006-09-14T03:43:00.000-07:00

In Computer security a denial-of-service attack (DoS attack) is an attempt to make a computer resource unavailable to its intended users. Typically the targets are high-profile web servers, the attack aiming to cause the hosted web pages to be unavailable on the Internet. It is a computer crime that violates the Internet proper use policy as indicated by the Internet Architecture Board (IAB).
DoS attacks have two general forms:
Force the victim computer(s) to reset or consume its resources such that it can no longer provide its intended service.
Obstruct the communication media between the intended users and the victim in such that they can no longer communicate adequately.
A "denial-of-service" attack is characterized by an explicit attempt by attackers to prevent legitimate users of a service from using that service. Examples include
attempts to "flood" a network, thereby preventing legitimate network traffic
attempts to disrupt connections between two machines, thereby preventing access to a service
attempts to prevent a particular individual from accessing a service
attempts to disrupt service to a specific system or person
Not all service outages, even those that result from malicious activity, are necessarily denial-of-service attacks. Other types of attack may include a denial of service as a component, but the denial of service may be part of a larger attack.
Illegitimate use of resources may also result in denial of service. For example, an intruder may use one's anonymous FTP area as a place to store illegal copies of commercial software, consuming disk space and generating network traffic.

Ajax: A New Approach to Web Applications

2006-09-14T02:14:00.000-07:00

By Jesse James Garrett

If anything about current interaction design can be called “glamorous,” it’s creating Web applications. After all, when was the last time you heard someone rave about the interaction design of a product that wasn’t on the Web? (Okay, besides the iPod.) All the cool, innovative new projects are online.
Despite this, Web interaction designers can’t help but feel a little envious of our colleagues who create desktop software. Desktop applications have a richness and responsiveness that has seemed out of reach on the Web. The same simplicity that enabled the Web’s rapid proliferation also creates a gap between the experiences we can provide and the experiences users can get from a desktop application.
That gap is closing. Take a look at Google Suggest. Watch the way the suggested terms update as you type, almost instantly. Now look at Google Maps. Zoom in. Use your cursor to grab the map and scroll around a bit. Again, everything happens almost instantly, with no waiting for pages to reload.
Google Suggest and Google Maps are two examples of a new approach to web applications that we at Adaptive Path have been calling Ajax. The name is shorthand for Asynchronous JavaScript + XML, and it represents a fundamental shift in what’s possible on the Web.
Defining Ajax
Ajax isn’t a technology. It’s really several technologies, each flourishing in its own right, coming together in powerful new ways. Ajax incorporates:
standards-based presentation using XHTML and CSS;
dynamic display and interaction using the Document Object Model;
data interchange and manipulation using XML and XSLT;
asynchronous data retrieval using XMLHttpRequest;
and JavaScript binding everything together.
The classic web application model works like this: Most user actions in the interface trigger an HTTP request back to a web server. The server does some processing — retrieving data, crunching numbers, talking to various legacy systems — and then returns an HTML page to the client. It’s a model adapted from the Web’s original use as a hypertext medium, but as fans of The Elements of User Experience know, what makes the Web good for hypertext doesn’t necessarily make it good for software applications.

Figure 1: The traditional model for web applications (left) compared to the Ajax model (right).
This approach makes a lot of technical sense, but it doesn’t make for a great user experience. While the server is doing its thing, what’s the user doing? That’s right, waiting. And at every step in a task, the user waits some more.
Obviously, if we were designing the Web from scratch for applications, we wouldn’t make users wait around. Once an interface is loaded, why should the user interaction come to a halt every time the application needs something from the server? In fact, why should the user see the application go to the server at all?
How Ajax is Different
An Ajax application eliminates the start-stop-start-stop nature of interaction on the Web by introducing an intermediary — an Ajax engine — between the user and the server. It seems like adding a layer to the application would make it less responsive, but the opposite is true.
Instead of loading a webpage, at the start of the session, the browser loads an Ajax engine — written in JavaScript and usually tucked away in a hidden frame. This engine is responsible for both rendering the interface the user sees and communicating with the server on the user’s behalf. The Ajax engine allows the user’s interaction with the application to happen asynchronously — independent of communication with the server. So the user is never staring at a blank browser window and an hourglass icon, waiting around for the server to do something.

Figure 2: The synchronous interaction pattern of a traditional web application (top) compared with the asynchronous pattern of an Ajax application (bottom).
Every user action that normally would generate an HTTP request takes the form of a JavaScript call to the Ajax engine instead. Any response to a user action that doesn’t require a trip back to the server — such as simple data validation, editing data in memory, and even some navigation — the engine handles on its own. If the engine needs something from the server in order to respond — if it’s submitting data for processing, loading additional interface code, or retrieving new data — the engine makes those requests asynchronously, usually using XML, without stalling a user’s interaction with the application.
Who’s Using Ajax
Google is making a huge investment in developing the Ajax approach. All of the major products Google has introduced over the last year — Orkut, Gmail, the latest beta version of Google Groups, Google Suggest, and Google Maps — are Ajax applications. (For more on the technical nuts and bolts of these Ajax implementations, check out these excellent analyses of Gmail, Google Suggest, and Google Maps.) Others are following suit: many of the features that people love in Flickr depend on Ajax, and Amazon’s A9.com search engine applies similar techniques.
These projects demonstrate that Ajax is not only technically sound, but also practical for real-world applications. This isn’t another technology that only works in a laboratory. And Ajax applications can be any size, from the very simple, single-function Google Suggest to the very complex and sophisticated Google Maps.
At Adaptive Path, we’ve been doing our own work with Ajax over the last several months, and we’re realizing we’ve only scratched the surface of the rich interaction and responsiveness that Ajax applications can provide. Ajax is an important development for Web applications, and its importance is only going to grow. And because there are so many developers out there who already know how to use these technologies, we expect to see many more organizations following Google’s lead in reaping the competitive advantage Ajax provides.
Moving Forward
The biggest challenges in creating Ajax applications are not technical. The core Ajax technologies are mature, stable, and well understood. Instead, the challenges are for the designers of these applications: to forget what we think we know about the limitations of the Web, and begin to imagine a wider, richer range of possibilities.
It’s going to be fun.

Ajax Q&A
March 13, 2005: Since we first published Jesse’s essay, we’ve received an enormous amount of correspondence from readers with questions about Ajax. In this Q&A, Jesse responds to some of the most common queries.
Q. Did Adaptive Path invent Ajax? Did Google? Did Adaptive Path help build Google’s Ajax applications?
A. Neither Adaptive Path nor Google invented Ajax. Google’s recent products are simply the highest-profile examples of Ajax applications. Adaptive Path was not involved in the development of Google’s Ajax applications, but we have been doing Ajax work for some of our other clients.
Q. Is Adaptive Path selling Ajax components or trademarking the name? Where can I download it?
A. Ajax isn’t something you can download. It’s an approach — a way of thinking about the architecture of web applications using certain technologies. Neither the Ajax name nor the approach are proprietary to Adaptive Path.
Q. Is Ajax just another name for XMLHttpRequest?
A. No. XMLHttpRequest is only part of the Ajax equation. XMLHttpRequest is the technical component that makes the asynchronous server communication possible; Ajax is our name for the overall approach described in the article, which relies not only on XMLHttpRequest, but on CSS, DOM, and other technologies.
Q. Why did you feel the need to give this a name?
A. I needed something shorter than “Asynchronous JavaScript+CSS+DOM+XMLHttpRequest” to use when discussing this approach with clients.
Q. Techniques for asynchronous server communication have been around for years. What makes Ajax a “new” approach?
A. What’s new is the prominent use of these techniques in real-world applications to change the fundamental interaction model of the Web. Ajax is taking hold now because these technologies and the industry’s understanding of how to deploy them most effectively have taken time to develop.
Q. Is Ajax a technology platform or is it an architectural style?
A. It’s both. Ajax is a set of technologies being used together in a particular way.
Q. What kinds of applications is Ajax best suited for?
A. We don’t know yet. Because this is a relatively new approach, our understanding of where Ajax can best be applied is still in its infancy. Sometimes the traditional web application model is the most appropriate solution to a problem.
Q. Does this mean Adaptive Path is anti-Flash?
A. Not at all. Macromedia is an Adaptive Path client, and we’ve long been supporters of Flash technology. As Ajax matures, we expect that sometimes Ajax will be the better solution to a particular problem, and sometimes Flash will be the better solution. We’re also interested in exploring ways the technologies can be mixed (as in the case of Flickr, which uses both).
Q. Does Ajax have significant accessibility or browser compatibility limitations? Do Ajax applications break the back button? Is Ajax compatible with REST? Are there security considerations with Ajax development? Can Ajax applications be made to work for users who have JavaScript turned off?
A. The answer to all of these questions is “maybe”. Many developers are already working on ways to address these concerns. We think there’s more work to be done to determine all the limitations of Ajax, and we expect the Ajax development community to uncover more issues like these along the way.
Q. Some of the Google examples you cite don’t use XML at all. Do I have to use XML and/or XSLT in an Ajax application?
A. No. XML is the most fully-developed means of getting data in and out of an Ajax client, but there’s no reason you couldn’t accomplish the same effects using a technology like JavaScript Object Notation or any similar means of structuring data for interchange.
Q. Are Ajax applications easier to develop than traditional web applications?
A. Not necessarily. Ajax applications inevitably involve running complex JavaScript code on the client. Making that complex code efficient and bug-free is not a task to be taken lightly, and better development tools and frameworks will be needed to help us meet that challenge.
Q. Do Ajax applications always deliver a better experience than traditional web applications?
A. Not necessarily. Ajax gives interaction designers more flexibility. However, the more power we have, the more caution we must use in exercising it. We must be careful to use Ajax to enhance the user experience of our applications, not degrade it.

ASP.NET Questions

2006-09-06T04:44:00.000-07:00

Why are you more likely to use HtmlControls rather than WebControls when migrating from ASP?
Choice 1
ASP pages are made from HTML elements, not controls, which map to the HtmlControls better.
Choice 2
HtmlControls involve less development effort.
Choice 3
HtmlControls have the same syntax as ASP HtmlControls.
Choice 4
HtmlControls can be used to transfer ASP session state.
Choice 5
ASP also uses HtmlControls.

In a Web application, how many security-related events does the global.asax file provide?
Choice 1
1
Choice 2
2
Choice 3
3
Choice 4
4
Choice 5
More than 4

Why does the Page object have an IsPostback property?
Choice 1
It is used to know that control events need to be thrown.
Choice 2
It is used in the Application_BeginRequest event to decide whether to authenticate a user.
Choice 3
It is used so that the Page can determine whether to load Viewstate.
Choice 4
It is used to determine whether to throw the Page_PostBack event.
Choice 5
It is used so that the controls can be loaded with their initial state when the page is first loaded.
ASP.NET Fundamentals, Question 10 of 40

A relationship between two DataTables within a DataSet is represented by which one of the following?
Choice 1
ForeignKey object
Choice 2
DataColumn object
Choice 3
DataTable object
Choice 4
PrimaryKey object
Choice 5
DataRelation object

Which one of the following do you use to add a new cookie to store a 'LastVisit' date with the current time?
Choice 1
Response.Cookies.Add( new HttpCookie("LastVisit", DateTime.Now.ToString()) );
Choice 2
Response.Cookies.Add( new Cookie("LastVisit", DateTime.Now.ToString()) );
Choice 3
Response.Add( new Cookie("LastVisit", DateTime.Now.ToString()) );
Choice 4
Response.Cookies.Add( new HttpCookie("LastVisit", DateTime.Now) );
Choice 5
Response.Add( new HttpCookie("LastVisit", DateTime.Now.ToString()) );

Assuming viewstate is enabled, what is wrong with the above code?
Choice 1
You need to check IsPostBack and bind the data only once.
Choice 2
The OnClick event fires before the Page_Load event.
Choice 3
The OnClick event does not fire until after the code is rendered.
Choice 4
The OnClick event will NEVER fire.
Choice 5
You cannot bind data in the Page_Load event.

Which object do you use as a means of reading a forward-only stream of rows when connecting to SQL Server 2000 database?
Choice 1
SqlServerDataAdapter
Choice 2
OleDbDataReader
Choice 3
SqlDataAdapter

Choice 4
OleDbDataAdapter
Choice 5
SqlDataReader

What line in the above control needs to be added for Wednesday to be selected by default?
Choice 1

Choice 2

Choice 3

Choice 4

Choice 5

Which server setting must be set in order to be able to store objects outside of a page in an application?
Choice 1
Enable application storage
Choice 2
Enable variable storage
Choice 3
Enable server-side variables
Choice 4
Enable session state
Choice 5
Enable Web forms

Under which one of the following situations is using a class inheriting from System.IO.Stream NOT appropriate?
Choice 1
Sending information across a network
Choice 2
Manipulating an XML DOM
Choice 3
Saving a file to disk
Choice 4
Loading a file from disk
Choice 5
Implementing a pipe
ASP.NET Fundamentals

Sample Code

For the code referenced above to work correctly in your application, in which one of the following directories does the compiled DLL from the file MyPage.aspx.cs need to be?
Choice 1
The same directory as the .aspx file calling it
Choice 2
The Web root for the application
Choice 3
/bin directory of the application
Choice 4
The Web root for the site
Choice 5
The directory named support

Assembly

2006-09-06T04:29:00.000-07:00

Assembly

In the Microsoft .NET framework an assembly is a partially compiled code library for use in deployment, versioning and security. In the Microsoft Windows implementation of .NET, an assembly is a PE (portable executable) file. There are two types, process assemblies (EXE) and library assemblies (DLL). A process assembly represents a process which will use classes defined in library assemblies. In version 1.1 of the CLR classes can only be exported from library assemblies; in version 2.0 this restriction is relaxed. The compiler will have a switch to determine if the assembly is a process or library and will set a flag in the PE file. .NET does not use the extension to determine if the file is a process or library. This means that a library may have either .dll or .exe as its extension.
The code in an assembly is compiled into CIL, which is then compiled into machine language at runtime by the CLR.
An assembly can consist of one or more files. Code files are called modules. An assembly can contain more than one code module and since it is possible to use different languages to create code modules this means that it is technically possible to use several different languages to create an assembly. In practice this rarely happens, principally because Visual Studio only allows developers to create assemblies that consist of a single code module.

Assembly Manifest

Every assembly, whether static or dynamic, contains a collection of data that describes how the elements in the assembly relate to each other. The assembly manifest contains this assembly metadata. An assembly manifest contains all the metadata needed to specify the assembly's version requirements and security identity, and all metadata needed to define the scope of the assembly and resolve references to resources and classes. The assembly manifest can be stored in either a PE file (an .exe or .dll) with Microsoft intermediate language (MSIL) code or in a standalone PE file that contains only assembly manifest information.

The Assembly Solution

2006-09-06T04:26:00.000-07:00

To solve versioning problems, as well as the remaining problems that lead to DLL conflicts, the runtime uses assemblies to do the following:
Enable developers to specify version rules between different software components.
Provide the infrastructure to enforce versioning rules.
Provide the infrastructure to allow multiple versions of a component to be run simultaneously (called side-by-side execution).

Major types of JavaScript

2006-09-01T04:27:00.000-07:00

There are 3 major types of JavaScript namely:

Client-Side JavaScript (CSJS) -- an extended version of JavaScript that enables the enhancement and manipulation of web pages and client browsersServer-Side JavaScript (SSJS) -- an extended version of JavaScript that enables back-end access to databases, file systems, and serversCore JavaScript -- the base JavaScript languageClient-Side JavaScript (CSJS) and Server-Side JavaScript (SSJS) are dependent on the core JavaScript and cannot work without it.

Client-Side JavaScriptClient-Side JavaScript (CSJS) is the single most popular language on the Internet, used in major web pages which are too numerous to be counted. CSJS is composed of core JavaScript and many additional objects, such as the following: document form frame window The objects in CSJS enable you to manipulate HTML documents (checking form fields, submitting forms, creating dynamic pages, and such) and the browser itself (directing the browser to load other HTML pages, display messages, and so on).Server-Side JavaScript Server-side JavaScript (SSJS) is composed of core JavaScript and additional objects and functions for accessing databases and file systems, sending e-mail, and so on. SSJS enables developers to quickly and easily create database-driven web applications by leveraging their existing knowledge of JavaScript. It's used to create and/or customize server-based applications by scripting the interaction between objects.SSJS is included with the Netscape Enterprise Server and is ideal for creating web applications that can be run on any platform, on any browser, and in any language. Why create something in Visual Basic or PowerBuilder that can be run on only one platform, when you can create a web application with SSJS that can be run on any existing platform (such as UNIX, Mac, and Windows) and even future platforms (like BEOS)? SSJS is also available in the Actra line of E-Commerce applications from Netscape, so that customers can customize their applications. The objects employed in the Actra implementation of SSJS are different from those used on the Enterprise Server because the data access engines are different. However, the core language is the same.

Client-side and Server-side JavaScript

2006-09-01T04:24:00.000-07:00

Client-side JavaScript (CSJS) is JavaScript that runs on client-side, i.e. the web browser, hence is for client-side scripting. While JavaScript was originally created to run on client-side, this term was coined because the language is no longer limited to just client-side, e.g. server-side JavaScript (SSJS) is also available.

Server-side JavaScript (SSJS) refers to JavaScript that runs on server-side. This term was coined because the language was originally limited to just client-side, i.e. client-side JavaScript (CSJS).

This article explains the three major types of JavaScript, client-side, server-side and the core language. Server-side JavaScript is ideal for creating web applications that can be run on any platform, on any browser, and in any language. See the article for other advantages and disadvantages of each.
Most people think that JavaScript is a form of Java, but that is not true. Java is a programming language developed by Sun Microsystems, while JavaScript was created by Netscape to extend the functions a browser can perform.
Uses of JavaScript:
Menus for Navigation
Form Validation
Popup Windows
Password Protecting
Math Functions
Special effects with document and background
Status bar manipulation
Messages
Mouse Cursor Effects

Web Service XML Output

2006-08-31T05:58:00.000-07:00

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Web;
using System.Web.Services;
using System.Configuration;
using System.IO;
using System.Data.SqlClient;
using System.Xml.Xsl;
using System.Xml;

namespace Xsl
{
///

/// Summary description for MyService.
///

public class MyService : System.Web.Services.WebService
{
public MyService()
{
//CODEGEN: This call is required by the ASP.NET Web Services Designer
InitializeComponent();
}
#region Component Designer generated code
//Required by the Web Services Designer
private IContainer components = null;
///

/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///

private void InitializeComponent()
{
}
///

/// Clean up any resources being used.
///

protected override void Dispose( bool disposing )
{
if(disposing && components != null)
{
components.Dispose();
}
base.Dispose(disposing);
}
#endregion
// WEB SERVICE EXAMPLE
// The HelloWorld() example service returns the string Hello World
// To build, uncomment the following lines then save and build the project
// To test this web service, press F5
[WebMethod]
public string CallServices()
{
string view = "";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand("select * from BrandMaster1 for xml raw",con);
con.Open();
XmlReader xr = cmd.ExecuteXmlReader();
xr.Read();
for(;xr.ReadState !=ReadState.EndOfFile;)
{
view += xr.ReadOuterXml();
}
view = "" + view + "";
XmlDocument xmldom = new XmlDocument();
XslTransform xsltrans = new XslTransform();
MemoryStream ms = new MemoryStream();
StreamReader sr = new StreamReader(ms);
xmldom.LoadXml(view);
xsltrans.Load(Server.MapPath("newservices.xsl"));
xsltrans.Transform(xmldom,null,ms,null);
ms.Seek(0,SeekOrigin.Begin);
//divXsl.InnerHtml = sr.ReadToEnd();
string retval = sr.ReadToEnd();
return retval;
}
[WebMethod]
public void CallEdit(int pkid,string brandcode,string brandname)
{
string conss = "update BrandMaster1 set BrandCode = '"+ brandcode.ToString() +"'" + ",BrandName = '"+ brandname + "'" + " where pkid = '"+ pkid +"'";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand(conss,con);
con.Open();
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
}
}
[WebMethod]
public void CallDelete(int pkid)
{
string conss = "delete from BrandMaster1 " + " where pkid = '"+ pkid +"'";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand(conss,con);
con.Open();
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
}
}
[WebMethod]
public string JavaScriptCall()
{
string view = "";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand("select * from BrandMaster1 for xml auto,elements",con);
con.Open();
XmlReader xr = cmd.ExecuteXmlReader();
xr.Read();
for(;xr.ReadState !=ReadState.EndOfFile;)
{
view += xr.ReadOuterXml();
}
view = "" + view + "";
return view;
}
[WebMethod]
public string CallStoredProc(string spName)
{
string view = "";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand(spName,con);
cmd.CommandType = CommandType.StoredProcedure;
con.Open();
XmlReader xr = cmd.ExecuteXmlReader();
xr.Read();
for(;xr.ReadState !=ReadState.EndOfFile;)
{
view += xr.ReadOuterXml();
}
view = "" + view + "";
return view;
}

[WebMethod]
public string CallAssign(int pkid)
{
string view = "";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand("select * from BrandMaster1 " + "where pkid '"+ pkid +"' ",con);
con.Open();
XmlReader xr = cmd.ExecuteXmlReader();
xr.Read();
for(;xr.ReadState !=ReadState.EndOfFile;)
{
view += xr.ReadOuterXml();
}
view = "" + view + "";
XmlDocument xmldom = new XmlDocument();
XslTransform xsltrans = new XslTransform();
MemoryStream ms = new MemoryStream();
StreamReader sr = new StreamReader(ms);
xmldom.LoadXml(view);
xsltrans.Load(Server.MapPath("newservices.xsl"));
xsltrans.Transform(xmldom,null,ms,null);
ms.Seek(0,SeekOrigin.Begin);
//divXsl.InnerHtml = sr.ReadToEnd();
string retval = sr.ReadToEnd();
return retval;
}
}
}

To bind xsl with xml in Javascript

2006-08-31T05:39:00.000-07:00

function callXMLXSLTransform(xmlStr,xslPath)
{
xml = new ActiveXObject("Microsoft.XMLDOM");
xml.async = false;
xml.load(xmlStr);
var xsl = new ActiveXObject("Microsoft.XMLDOM");
xsl.async = false;
xsl.load(xslPath);
return xml.transformNode(xsl);
}

JavaScript ProjWS-3

2006-07-25T04:33:00.000-07:00

callWebServiceDisplay();

function callWebServiceDisplay()
{
var httpObj = new ActiveXObject("MSXml2.XMLHTTP");
httpObj.open("POST","http://localhost/Diageeo/Xsl/MyService.asmx",false);
httpObj.setRequestHeader("SOAPAction","http://tempuri.org/CallServices");
httpObj.setRequestHeader("Content-Type","text/xml");
httpObj.send(getMy());
alert(httpObj.responseText);
// alert(httpObj.responseText);
var jj = encodeXml(httpObj.responseText);
divDisplay.innerHTML = jj;
return httpObj.responseText;
}

function encodeXml(str){
//str = str.replace(/&/gi, "&");
str = str.replace(/</gi, "<"); str = str.replace(/>/gi, ">");
return str;
}

function getMy()
{
var obj = "";
obj = "string";
alert(obj);
return obj;
}

XSL ProjWS-2

2006-07-25T04:32:00.000-07:00

PKID	BrandCode	Edit BrandName	Delete BrandName
		javascript:EditLoad('')	javascript:DeleteLoad('')

XSL ProjWS-2

2006-07-25T04:31:00.000-07:00

My CD Collection

Title	Artist

Web service for Transformation ProjWS -1

2006-07-25T04:25:00.001-07:00

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Web;
using System.Web.Services;

using System.Configuration;
using System.IO;
using System.Data.SqlClient;
using System.Xml.Xsl;
using System.Xml;

namespace Xsl
{
///

/// Summary description for MyService.
///

public class MyService : System.Web.Services.WebService
{
public MyService()
{
//CODEGEN: This call is required by the ASP.NET Web Services Designer
InitializeComponent();
}

#region Component Designer generated code

//Required by the Web Services Designer
private IContainer components = null;

///

/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///

private void InitializeComponent()
{
}

///

/// Clean up any resources being used.
///

protected override void Dispose( bool disposing )
{
if(disposing && components != null)
{
components.Dispose();
}
base.Dispose(disposing);
}

#endregion

// WEB SERVICE EXAMPLE
// The HelloWorld() example service returns the string Hello World
// To build, uncomment the following lines then save and build the project
// To test this web service, press F5

[WebMethod]
public string CallServices()
{
string view = "";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand("select * from BrandMaster1 for xml raw",con);
con.Open();
XmlReader xr = cmd.ExecuteXmlReader();
xr.Read();
for(;xr.ReadState !=ReadState.EndOfFile;)
{
view += xr.ReadOuterXml();
}
view = "" + view + "";
XmlDocument xmldom = new XmlDocument();
XslTransform xsltrans = new XslTransform();
MemoryStream ms = new MemoryStream();
StreamReader sr = new StreamReader(ms);
xmldom.LoadXml(view);
xsltrans.Load(Server.MapPath("newservices.xsl"));
xsltrans.Transform(xmldom,null,ms,null);
ms.Seek(0,SeekOrigin.Begin);
//divXsl.InnerHtml = sr.ReadToEnd();

string retval = sr.ReadToEnd();

return retval;
}
[WebMethod]
public void CallEdit(int pkid,string brandcode,string brandname)
{
string conss = "update BrandMaster1 set BrandCode = '"+ brandcode.ToString() +"'" + ",BrandName = '"+ brandname + "'" + " where pkid = '"+ pkid +"'";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand(conss,con);
con.Open();
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
}
}

[WebMethod]
public void CallDelete(int pkid)
{
string conss = "delete from BrandMaster1 " + " where pkid = '"+ pkid +"'";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand(conss,con);
con.Open();
SqlDataReader dr = cmd.ExecuteReader();
while (dr.Read())
{
}

}

[WebMethod]
public string CallAssign(int pkid)
{
string view = "";
SqlConnection con = new SqlConnection(ConfigurationSettings.AppSettings["constring"]);
SqlCommand cmd = new SqlCommand("select * from BrandMaster1 " + "where pkid '"+ pkid +"' ",con);
con.Open();
XmlReader xr = cmd.ExecuteXmlReader();
xr.Read();
for(;xr.ReadState !=ReadState.EndOfFile;)
{
view += xr.ReadOuterXml();
}
view = "" + view + "";
XmlDocument xmldom = new XmlDocument();
XslTransform xsltrans = new XslTransform();
MemoryStream ms = new MemoryStream();
StreamReader sr = new StreamReader(ms);
xmldom.LoadXml(view);
xsltrans.Load(Server.MapPath("newservices.xsl"));
xsltrans.Transform(xmldom,null,ms,null);
ms.Seek(0,SeekOrigin.Begin);
//divXsl.InnerHtml = sr.ReadToEnd();

string retval = sr.ReadToEnd();

return retval;
}

}
}

Calling the Server-Side method asynchronously from Client Script

2006-07-25T02:44:00.000-07:00

Client Callbacks

Author

Dipen Lama

Client Callbacks is a new feature of ASP.NET 2 which allow client side script to call server side method asynchronously without post back to fetch new data from server and change the display in client brower dynamically.

Developer use JavaScript mainly to make the page more interactive and to avoid page postback. But there are often situation where post back of page is necessary to fetch new data from the server/database. Consider a scenerio where we have a dropdown list of Countries and a listbox of the cities. The listbox cities should display the cities based on the selected country from the dropdown list.

Now in this case we have to post back the page when the Country dropdown item is changes and fill the Cities listbox with the new items fetched form the database based on the Country selected. The simple way to do avoid postback is to use Client Callbacks where the JavaScript code will communicate with the server and refresh the Cities listbox without postback.

The following procedure has to be followed to create Client Callbacks:

Step 1:

To receive the call back from the client the page must implement the ICallbackEventHandler interface.

public partial class ClientCallbackPage : System.Web.UI.Page, ICallbackEventHandler

{

}

Step 2:

The ICallbackEventHandler has two methods RaiseCallBackEvent() that receives data from the client browser as a string agrument which is triggered first and GetCallbackResult() that provides the data to the client browser and is trigger next.

In our example, we will pass the Selected Country value to the server in the RaiseCallBackEvent()

public void RaiseCallbackEvent(string callbackEventArgument)

{

m_callbackEventArgument = callbackEventArgument;
}

m_callbackEventArgument is a private string member variable and we will assign the selected country value passed from the client browser on it. Now in the GetCallbackResult() method we can retrieve the cities list for the selected country from the database or any other datastore and passed the cities list back to the client browser. Here in this example I have just hardcoded the cities list that is suppose to come from database.

public string GetCallbackResult()

{

string callbackResult = String.Empty;

if (m_callbackEventArgument.Equals("India"))

{

callbackResult += "New Delhi|New
Delhi;Mumbai|Mumbai;Kolkata|Kolkata;";

}

if (m_callbackEventArgument.Equals("China"))

{

callbackResult += "Bejing|Bejing;Shanghai|Shanghai;Xian|Xian;";

}

return callbackResult;
}

The main limitation of ASP.NET Client Callback is that you can send data to the client only as a single string. So, we are sending the cities list to the client browser as string seperated with ";" character and "|" character to separte the text and value field of the city. If you have to pass a complex data such as your collection of business object data then you need to design a way to serialize the data into string and deserialize the string on the client browser with JavaScript. One way is have a xml string and passed it and on the client side it can be parsed with JavaScript either with the built in xml parser or your own.

Step 3:

The third step is to write a client script which will receive the data from the server and deserialize it and display it on the browser. We can give any name to the JavaScript method which handles the callback response from the server but should have two arguments.

function ClientCallbackScript(result, context)

{

var lstCity = document.forms[0].elements['lstCity'];

lstCity.innerHTML= "";

var cities = result.split(';');

for (var i = 0; i < cities.length - 1; ++i)

{

var properties = cities[i].split('|');

var cityName = properties[0];

var cityId = properties[1];

var option = document.createElement("option");

option.value = cityId;

option.innerHTML = cityName;

lstCity.appendChild(option);

}
}

Here the result parameter holds the data that is send by the server and now this has to be parsed and filled up in the cities listbox.

Step 4:

Now the final step is to define the event in which the Callback trigger is fired. Here in our case we will define the Callback trigger to fire on the Country dropdown list changed event.

protected void Page_Load(object sender, EventArgs e)

{

if (! Page.IsPostBack)

{

FillCountryList();

FillCityList(ddlCountry.SelectedValue);

string callbackEventReference =
Page.ClientScript.GetCallbackEventReference(this,
"document.all['ddlCountry'].value", "ClientCallbackScript",
"null");

ddlCountry.Attributes["onclick"] = callbackEventReference;

}
}

The Page.ClientScript.GetCallbackEventReference returns a JavaScript code that calls the Client Callback. The first agruments it take is the ICallBackEventHandler object that will handle the callback that is the page itself in our case. The second argument is the data that the client browser will pass to the server i.e selected Country from the dropdown list. The third argument is the name of the JavaScript method that will receive the data from the server callback. And the last argument is the Context information that we want to pass. Here we are passing null.

Below is the complete sequence diagram of the above process

About the author
Dipen Lama

Dipen is a .Net Developer and has over 3yrs of experience in ASP.NET, VB.NET and C#. Dipen interest is in Smart Client, DotNetNuke, Sharepoint Webpart and Atlas

Multi Lingual page ASP.NET

2006-05-31T03:52:00.000-07:00

Here the commented part would be the client side calling in ASP.NET file

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.Resources;

namespace NewMultiLingual
{
///

/// Summary description for WebForm1.
///

public class WebForm1 : System.Web.UI.Page
{
protected System.Web.UI.WebControls.Literal usernameLabel;
protected System.Web.UI.WebControls.TextBox username;
protected System.Web.UI.WebControls.Literal passwordLabel;
protected System.Web.UI.WebControls.TextBox password;
protected System.Web.UI.WebControls.Button login;

private void Page_Load(object sender, System.EventArgs e)
{
ResourceManager Rm1 = new ResourceManager("NewMultiLingual.Resource",System.Reflection.Assembly.GetExecutingAssembly());
usernameLabel.Text = Rm1.GetString("Username");
passwordLabel.Text = Rm1.GetString("Password");
login.Text = Rm1.GetString("Login");
// Put user code to initialize the page here
}

#region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}

///

/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///

private void InitializeComponent()
{
this.Load += new System.EventHandler(this.Page_Load);

}
#endregion
}
}

Make Global.asax.cs

protected void Application_BeginRequest(Object sender, EventArgs e)
{

string lang = Request.QueryString["lang"];
string culturename = "en-US";
if (lang!= " ")
{
switch(lang)
{
case "f":
culturename = "fr-CA";
break;

case "ca":
culturename = "en-CA";
break;

case "ta":
culturename = "ta-IN";
break;

// default:
// culturename = "en-US" ;
}

}

CultureInfo Ci = new CultureInfo(culturename);
//Thread.CurrentThread.CurrentCulture = Ci;
Thread.CurrentThread.CurrentUICulture = Ci;

}

make appropriate additions in resource files

Spell Check Software

2006-05-18T04:19:00.000-07:00

First add a reference of Microsoft word object library

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;
namespace SpellBound1
{
///

/// Summary description for Form1.
///

public class Form1 : System.Windows.Forms.Form
{
private System.Windows.Forms.TextBox textBox1;
private System.Windows.Forms.Button button1;
private System.Windows.Forms.Label label1;
private System.Windows.Forms.Label label2;
///

/// Required designer variable.
///

private System.ComponentModel.Container components = null;
public Form1()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//
// TODO: Add any constructor code after InitializeComponent call
//
}
///

/// Clean up any resources being used.
///

protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}
#region Windows Form Designer generated code
///

/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///

private void InitializeComponent()
{
this.textBox1 = new System.Windows.Forms.TextBox();
this.button1 = new System.Windows.Forms.Button();
this.label1 = new System.Windows.Forms.Label();
this.label2 = new System.Windows.Forms.Label();
this.SuspendLayout();
//
// textBox1
//
this.textBox1.Location = new System.Drawing.Point(24, 80);
this.textBox1.Name = "textBox1";
this.textBox1.Size = new System.Drawing.Size(168, 20);
this.textBox1.TabIndex = 0;
this.textBox1.Text = "";
//
// button1
//
this.button1.Location = new System.Drawing.Point(240, 80);
this.button1.Name = "button1";
this.button1.TabIndex = 1;
this.button1.Text = "Check";
this.button1.Click += new System.EventHandler(this.button1_Click);
//
// label1
//
this.label1.Font = new System.Drawing.Font("Microsoft Sans Serif", 9.75F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
this.label1.Location = new System.Drawing.Point(24, 32);
this.label1.Name = "label1";
this.label1.Size = new System.Drawing.Size(296, 32);
this.label1.TabIndex = 2;
this.label1.Text = "Enter a word or sentence to check the spelling";
//
// label2
//
this.label2.Font = new System.Drawing.Font("Microsoft Sans Serif", 9.75F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));
this.label2.Location = new System.Drawing.Point(24, 112);
this.label2.Name = "label2";
this.label2.Size = new System.Drawing.Size(288, 23);
this.label2.TabIndex = 3;
this.label2.Click += new System.EventHandler(this.label2_Click);
//
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(400, 149);
this.Controls.Add(this.label2);
this.Controls.Add(this.label1);
this.Controls.Add(this.button1);
this.Controls.Add(this.textBox1);
this.Name = "Form1";
this.Text = "Form1";
this.Load += new System.EventHandler(this.Form1_Load);
this.ResumeLayout(false);
}
#endregion
///

/// The main entry point for the application.
///

[STAThread]
static void Main()
{
Application.Run(new Form1());
}

private void button1_Click(object sender, System.EventArgs e)
{
string strchk = textBox1.Text;
Boolean bresult;
string strreturn;
string res;
Object filler = null;
Word.Application appword = null;
try
{
appword = new Word.ApplicationClass();
bresult = appword.CheckSpelling(strchk,ref filler,ref filler,ref filler,ref filler,ref filler,ref filler,ref filler,ref filler,ref filler,ref filler,ref filler,ref filler);
if(bresult == true)
{
res = "correct";
}
else
{
res = "not correct";
}
strreturn = "The given text is " + res;
}
catch(Exception Ex)
{
strreturn = "Exception occured "+ Ex.Message;
}
finally
{
if(appword!=null)
{
appword.Quit(ref filler,ref filler,ref filler);
}
}
label2.Text = strreturn;
}
}
}

Web applications vs Client-Server Applications

2006-04-23T21:24:00.000-07:00

Web applications vs Client-Server Applications

In this article I discuss the differences between thin (web-based) clients and thick (desktop) clients, and attempt to help
answer an often asked question: "Should this business system we want to develop be a web-application?"
Web applications, sometimes called "thin client" solutions, are concerned with performing business tasks through a web
interface. Usually, this involves viewing and manipulating data in a database.

They are typically deployed on an intranet or extranet, with access restricted by passwords or other methods.

Client-Server applications, or "Thick Client" solutions, are the more traditional way of doing things. The "server" side
often has a "middle layer" inbetween the client and the database, this is called a "3-tier" solution. Sometimes there are
multiple middle layers which interract, and this is called an "n-tier" solution. Sometimes there are thin-clients and thickclients
interracting with the same back-end systems.

Larger systems will sometimes have a combination of thin-client and thick-client front-ends which interract with various
bits of "middleware" that in turn interract with one or more databases.

In this article I will ignore the server side and focus on the differences between thin (web-based) clients and thick
(desktop) clients, and I will attempt to help answer a question often asked "Should this business system we want to
develop be a web-application?"

h2. Points to consider:

h3. Flexibility in interface design

How often witll the users be using the system? Essentially the more the system gets used and the more complex the
tasks the greater opportunity to take advantage of the richer set of controls available in a thick-client.

Modern browsers allow for a much richer range of interraction than was possible previously, but it's still a lot easier to
design a good user interface using a desktop application design system. It simply takes a lot of javacript to acheive
some of what is easy in a visual development enviromnent like VB or Delphi.

There are a much larger collection of components available for
Precise positioning of controls/windows, sizing of fonts, etc, is a little easier with a desktop app.

It's much easier to do realtime screen updates with a desktop app. For instance updating a view of matching records
from a "find" field in realtime - an invaluable feature in Mozilla's mail applications.
Slider bars, gauges, pop-up calendars, extensive-menuing, dockable-windows, tree-widgets, etc, are easier to implement
on a thick-client.

Many of these can be done with ActiveX or Java based controls for a web app, but it requires more time and effort than a
desktop app, and the result tends to be "clunkier".

h3. Reports
* Do your reports have complex printing requirements? (eg multiple printers, multiple sizes, landscape vs portrait,
controlled pagination) These are considerably more diffcult to handle with a web-application.

h3. Usage
# How many hours/minutes will staff spend using this application every week?
* The more time spent in the application, the more likely it's worth going to the extra level of customization offered by a
desktop app.

Deployment Issues

# How distributed are your staff?
# How many of them are there?
# Are they technically literate? Would you trust them to update a thick-client on their own?
* Web applications do not need to be installed and upgraded across many PC's, saving time and hassle.
* Thick client software can include the ability to self-update over the internet. This is not trivial to implement, however,
and may cause unpredictable problems on some computers.
* If the software is likely to be regularly updated, web-applications or self-updating thick clients will save a lot of time.

http://apposite.co.nz/apposite - Apposite Internet Solutions Powered by Mambo Open Source Generated: 24 April, 2006, 16:13
h3. Do your staff all use the same operating system?

* Multiple operating systems make problems for desktop apps just as multiple browser types make problems for webapplications.
Differences between windows versions can usually be handled, differences between Windows, Mac, and
Unix usually require considerable effort to handle!

* Writing a desktop app that works on windows and macs more or less requires using Java, and it's difficult to make the
interface comfortable to either, let alone both. In some cases writing one client for each may be a better solution.
* Microsoft's .NET platform may also work on multiple O/S's in the future but will have it's own pitfalls.

* The usual hurdle that has to be faced is writing for different versions of windows - many old applications do not work
well on Microsoft XP, and applications written for NT/2000/XP sometimes have trouble running on Win9x/ME

h3. Do your staff all use the same web browser?

* I don't recommend attempting to deploy web-applications if the users are using Netscape 4.x or IE3.x, but if anyone is
still using these browsers upgrading them should be a priority as half the web is probably looking broken right now.
* These days no one would consider writing a web-application for Netscape 4.x, it has too many bugs in it's dynamic html
engine, and it is not at all standards-compliant. Writing for IE4+ or IE5+ has fewer pitfalls.
Netscape 6/7 and Mozilla 1.x are broadly compatible with IE5+ but there will be a few small issues to sort out.
* Do note that IE for Mac is a different browser to IE for Windows from the point of view of a web application.

Do your staff always work at the same PC or do they move around?

* Web applications have the advantage of being available from anywhere, and any personalisation features are available
from wherever the user is.
* But web applications will sometimes run into trouble if the web-browser is not configured properly for the application -
this problem can be minimised if the web application is designed to run in multiple environments.

h3. Security Issues

* Web applications that may be used in a shared enviroment obviously have security implications. For instance many
browsers allow you to save passwords, and if this is done subsequent users of the browser may find they can access the
application.

h3. Key points

h4. Key Advantages for Client-Server Applications
* Flexibility in interface design
* Speed in execution

h4. Key Advantages for Web Applications
* Ease of deployment
* Ease of software updates

h3. How to get the best of both worlds?

Don't put all your eggs in one basket. Deploy smaller applications that accomplish different tasks, eg data-entry, dataanalysis,
and reporting. Look at the specifics of each task, and see whether a web-application is more suitable. However
this may involve using multiple solution providers, which has it's own pitfalls. If you can find a company that has abilities
in both toolsets, they may well suggest such a hybrid themselves.

h4. Key points if using a hybrid approach:
* Store all your data in one location to avoid the hassles of duplication, inconsistency, and double-entry.
* Use a client-server database. File based databases are inadequate for multiple access applications and will usually just
lead to grief.

h4. "Rich" Web Applications

Java - Embedding Java Applets into a web pages allows one to add fancier functionality at the cost of increased
download time and reduced compatibility. In some csaes it's absolutely appropriate.

XUL - This is a widget toolset built into Mozilla based web browsers. I've never tried it, but potentially this will give you all
the advantages of DHTML applications with a but with a much larger set of controls. You'll need to find an experienced
developer, and your userbased will need to be standardised on a Mozilla client - I recommend
http://apposite.co.nz/apposite - Apposite Internet Solutions Powered by Mambo Open Source Generated: 24 April, 2006, 16:13
"Firefox":http://www.mozilla.org/products/firefox/

* If you want some advice on a specific project, contact me.
http://apposite.co.nz/apposite - Apposite Internet Solutions Powered by Mambo Open Source Generated: 24 April, 2006, 16:13

FAQ

2006-04-19T04:41:00.000-07:00

ASP.NET

Why asp.net?

Enhanced Performance.
World-Class Tool Support.
Power and Flexibility.
Simplicity.
Manageability.
Scalability and Availability.
Customizability and Extensibility.
Security.

And

http://www.dotnetjunkies.com/quickstart/aspplus/doc/whatisaspx.aspx

xml

2006-04-09T23:13:00.000-07:00

Introduction

The Extensible Markup Language (XML) was originally envisioned as a language for defining new document formats for the World Wide Web. XML is derived from the Standard Generalized Markup Language (SGML), and can be considered to be a meta-language: a language for defining markup languages.

Advantages

XML-

was designed to describe data
tags are not predefined. You must define your own tags
uses a Document Type Definition (DTD) or an XML Schema to describe the data
with a DTD or XML Schema is designed to be self-descriptive
is a W3C Recommendation

Conclusion

XML is more than just a text format for describing documents. It brings us one step closer to universal data access.

What Is MSXML?

Microsoft XML Core Services (MSXML) allows customers to build high-performance XML-based applications that provide a high degree of interoperability with other applications that adhere to the XML 1.0 standard.

Links

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnxml/html/UnderstXML.asp

Pointers

2006-04-03T05:04:00.000-07:00

Pointers:
"Pointers

Pointer are a fundamental part of C. If you cannot use pointers properly then you have basically lost all the power and flexibility that C allows. The secret to C is in its use of pointers.
C uses pointers a lot. Why?:
It is the only way to express some computations.
It produces compact and efficient code.
It provides a very powerful tool.
C uses pointers explicitly with:
Arrays,
Structures,
Functions.
NOTE: Pointers are perhaps the most difficult part of C to understand. C's implementation is slightly different DIFFERENT from other languages. "

What is a pointer?
One of those things beginners in C find difficult is the concept of pointers. The purpose of this tutorial is to provide an introduction to pointers and their use to these beginners.
I have found that often the main reason beginners have a problem with pointers is that they have a weak or minimal feeling for variables, (as they are used in C). Thus we start with a discussion of C variables in general.
A variable in a program is something with a name, the value of which can vary. The way the compiler and linker handles this is that it assigns a specific block of memory within the computer to hold the value of that variable. The size of that block depends on the range over which the variable is allowed to vary. For example, on 32 bit PC's the size of an integer variable is 4 bytes. On older 16 bit PCs integers were 2 bytes. In C the size of a variable type such as an integer need not be the same on all types of machines. Further more there is more than one type of integer variable in C. We have integers, long integers and short integers which you can read up on in any basic text on C. This document assumes the use of a 32 bit system with 4 byte integers.
If you want to know the size of the various types of integers on your system, running the following code will give you that information.
#include
int main(){printf("size of a short is %d\n", sizeof(short));printf("size of a int is %d\n", sizeof(int));printf("size of a long is %d\n", sizeof(long));}
When we declare a variable we inform the compiler of two things, the name of the variable and the type of the variable. For example, we declare a variable of type integer with the name k by writing: int k;
On seeing the "int" part of this statement the compiler sets aside 4 bytes of memory (on a PC) to hold the value of the integer. It also sets up a symbol table. In that table it adds the symbol k and the relative address in memory where those 4 bytes were set aside.
Thus, later if we write: k = 2;
we expect that, at run time when this statement is executed, the value 2 will be placed in that memory location reserved for the storage of the value of k. In C we refer to a variable such as the integer k as an "object".
In a sense there are two "values" associated with the object k. One is the value of the integer stored there (2 in the above example) and the other the "value" of the memory location, i.e., the address of k. Some texts refer to these two values with the nomenclature rvalue (right value, pronounced "are value") and lvalue (left value, pronounced "el value") respectively.
In some languages, the lvalue is the value permitted on the left side of the assignment operator '=' (i.e. the address where the result of evaluation of the right side ends up). The rvalue is that which is on the right side of the assignment statement, the 2 above. Rvalues cannot be used on the left side of the assignment statement. Thus: 2 = k; is illegal.
Actually, the above definition of "lvalue" is somewhat modified for C. According to K&R II (page 197): [1]
"An object is a named region of storage; an lvalue is an expression referring to an object."
However, at this point, the definition originally cited above is sufficient. As we become more familiar with pointers we will go into more detail on this.
Okay, now consider: int j, k;
k = 2;
j = 7; <-- line 1 k = j; <-- line 2 In the above, the compiler interprets the j in line 1 as the address of the variable j (its lvalue) and creates code to copy the value 7 to that address. In line 2, however, the j is interpreted as its rvalue (since it is on the right hand side of the assignment operator '='). That is, here the j refers to the value stored at the memory location set aside for j, in this case 7. So, the 7 is copied to the address designated by the lvalue of k. In all of these examples, we are using 4 byte integers so all copying of rvalues from one storage location to the other is done by copying 4 bytes. Had we been using two byte integers, we would be copying 2 bytes. Now, let's say that we have a reason for wanting a variable designed to hold an lvalue (an address). The size required to hold such a value depends on the system. On older desk top computers with 64K of memory total, the address of any point in memory can be contained in 2 bytes. Computers with more memory would require more bytes to hold an address. The actual size required is not too important so long as we have a way of informing the compiler that what we want to store is an address. Such a variable is called a pointer variable (for reasons which hopefully will become clearer a little later). In C when we define a pointer variable we do so by preceding its name with an asterisk. In C we also give our pointer a type which, in this case, refers to the type of data stored at the address we will be storing in our pointer. For example, consider the variable declaration: int *ptr; ptr is the name of our variable (just as k was the name of our integer variable). The '*' informs the compiler that we want a pointer variable, i.e. to set aside however many bytes is required to store an address in memory. The int says that we intend to use our pointer variable to store the address of an integer. Such a pointer is said to "point to" an integer. However, note that when we wrote int k; we did not give k a value. If this definition is made outside of any function ANSI compliant compilers will initialize it to zero. Similarly, ptr has no value, that is we haven't stored an address in it in the above declaration. In this case, again if the declaration is outside of any function, it is initialized to a value guaranteed in such a way that it is guaranteed to not point to any C object or function. A pointer initialized in this manner is called a "null" pointer. The actual bit pattern used for a null pointer may or may not evaluate to zero since it depends on the specific system on which the code is developed. To make the source code compatible between various compilers on various systems, a macro is used to represent a null pointer. That macro goes under the name NULL. Thus, setting the value of a pointer using the NULL macro, as with an assignment statement such as ptr = NULL, guarantees that the pointer has become a null pointer. Similarly, just as one can test for an integer value of zero, as in if(k == 0), we can test for a null pointer using if (ptr == NULL). But, back to using our new variable ptr. Suppose now that we want to store in ptr the address of our integer variable k. To do this we use the unary & operator and write: ptr = &amp;amp;amp;k; What the & operator does is retrieve the lvalue (address) of k, even though k is on the right hand side of the assignment operator '=', and copies that to the contents of our pointer ptr. Now, ptr is said to "point to" k. Bear with us now, there is only one more operator we need to discuss. The "dereferencing operator" is the asterisk and it is used as follows: *ptr = 7; will copy 7 to the address pointed to by ptr. Thus if ptr "points to" (contains the address of) k, the above statement will set the value of k to 7. That is, when we use the '*' this way we are referring to the value of that which ptr is pointing to, not the value of the pointer itself. Similarly, we could write: printf("%d\n",*ptr); to print to the screen the integer value stored at the address pointed to by ptr;. One way to see how all this stuff fits together would be to run the following program and then review the code and the output carefully. ------------ Program 1.1 --------------------------------- /* Program 1.1 from PTRTUT10.TXT 6/10/97 */ #include
int j, k;
int *ptr;
int main(void)
{
j = 1;
k = 2;
ptr = &k;
printf("\n");
printf("j has the value %d and is stored at %p\n", j, (void *)&j);
printf("k has the value %d and is stored at %p\n", k, (void *)&k);
printf("ptr has the value %p and is stored at %p\n", ptr, (void *)&ptr);
printf("The value of the integer pointed to by ptr is %d\n", *ptr);
return 0;
}
Note: We have yet to discuss those aspects of C which require the use of the (void *) expression used here. For now, include it in your test code. We'll explain the reason behind this expression later.
To review:
A variable is declared by giving it a type and a name (e.g. int k;)
A pointer variable is declared by giving it a type and a name (e.g. int *ptr) where the asterisk tells the compiler that the variable named ptr is a pointer variable and the type tells the compiler what type the pointer is to point to (integer in this case).
Once a variable is declared, we can get its address by preceding its name with the unary & operator, as in &k.
We can "dereference" a pointer, i.e. refer to the value of that which it points to, by using the unary '*' operator as in *ptr.
An "lvalue" of a variable is the value of its address, i.e. where it is stored in memory. The "rvalue" of a variable is the value stored in that variable (at that address).

Automatic memory management

Automatic memory management is one of the services that the common language runtime provides during Managed Execution. The common language runtime's garbage collector manages the allocation and release of memory for an application. For developers, this means that you do not have to write code to perform memory management tasks when you develop managed applications. Automatic memory management can eliminate common problems, such as forgetting to free an object and causing a memory leak, or attempting to access memory for an object that has already been freed. This section describes how the garbage collector allocates and releases memory.

Techniques

Optimal memory managers would be common if they were easily built. They are scarce, so you can expect that a variety of subtle techniques are needed even to approach the optimum.
One such technique is to treat different request sizes differently. In most programs, small blocks are requested overwhelmingly more often than large blocks, so both time and space overhead for them is felt disproportionately.
Another technique results from noting that there are only a few different sizes possible for very small blocks, so that each such size may be handled separately. We can even afford to keep a vector of free block lists for those few sizes.
A third is to avoid system call overhead by requesting memory from the operating system in big chunks, and by not touching unused (and possibly paged-out) blocks unnecessarily. This means data structures consulted to find a block to allocate should be stored compactly, apart from the unused blocks they describe.
The final, and most important, technique is to exploit address arithmetic which, while not strictly portable according to language standards, works well on all modern flat-memory architectures. A pointer value can be treated as an integer, and bitwise logical operations may be used on it to yield a new pointer value. In particular, the low bits may be masked off to yield a pointer to a header structure that describes the block pointed to. In this way a block need not contain a pointer to that information. Furthermore, many blocks can share the same header, amortizing its overhead across all. (This technique is familiar in the LISP community, where it is known as "page-tagging".)

Pointers

Pointers are special kinds of variables. There are three kinds of pointers supported by the runtime: managed pointers, unmanaged pointers, and unmanaged function pointers.
A managed pointer, also known as a __gc pointer, is a new type of pointer available to managed applications. Managed pointers are references to a managed block of memory from the common language runtime heap. Automatic garbage collection is performed on this heap. Managed pointers are generated for method arguments that are passed by reference. Some languages provide other ways of generating managed pointers. Only managed pointers are CLS-compliant.
An unmanaged pointer is the traditional C++ pointer to an unmanaged block of memory from the standard C++ heap. Because unmanaged pointers are not part of the Common Language Specification (CLS), your language might not provide syntax to define or access these types. See the documentation for your language for information on support for unmanaged pointers.
An unmanaged function pointer is also a traditional C++ pointer that refers to the address of a function. The CLS provides delegates as a managed alternative to unmanaged function pointers.
An explicit definition of a pointer type is not required. All the information necessary to determine the type of a pointer is present when the pointer is declared.
While pointer types are reference types, the value of a pointer type is not an object and you cannot determine the exact type from such a value.

References:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/cpguide/html/cpconautomaticmemorymanagement.asp

http://home.netcom.com/~tjensen/ptr/ch1x.htm

http://www.cantrip.org/wave12.html

http://www.augustcouncil.com/~tgibson/tutorial/ptr.html

http://www.augustcouncil.com/~tgibson/tutorial/ptr.html

ASP.NET

2006-03-28T01:51:00.000-08:00

Blog on ASP.NET

New in ASP .NET

Better language support
Programmable controls
Event-driven programming
XML-based components
User authentication, with accounts and roles
Higher scalability
Increased performance - Compiled code
Easier configuration and deployment
Not fully ASP compatible

Language Support

ASP .NET uses the new ADO .NET.
ASP .NET supports full Visual Basic, not VBScript.
ASP .NET supports C# (C sharp) and C++.
ASP .NET supports JScript as before.

C#

2006-03-28T01:40:00.000-08:00

Namespaces

Namespaces are C# program elements designed to help you organize your programs. They also provide assistance in avoiding name clashes between two sets of code.

JavaScript

2006-03-27T20:50:00.000-08:00

Javascript and jscript are different kind and from different companies

To call a control from javascript

function gObj(id)
{
return document.getElementById(id);
}

To disable a control and release it from disable

function jsfReadOnly(inputCtl) {
var controls = jsfChildElements(inputCtl);
for(var i = 0; i < controls.length; i++) {
if(controls[i].type == "text" controls[i].type.match("^select") controls[i].type.match("^checkbox") controls[i].type.match("^textarea") ) {
controls[i].disabled=true;
}
}
}

function jsfReleaseReadOnly(inputCtl) {
var controls = jsfChildElements(inputCtl);
for(var i = 0; i < controls.length; i++) {
if(controls[i].type == "text" controls[i].type.match("^select") controls[i].type.match("^checkbox") controls[i].type.match("^textarea") ) {
controls[i].disabled=false;
}
}
}

.net FAQ

2006-03-27T03:51:00.000-08:00

ASP.NET Page Life Cycle

What is an assembly?

An assembly is sometimes described as a logical .EXE or .DLL, and can be an application (with a main entry point) or a library. An assembly consists of one or more files (dlls, exes, html files etc), and represents a group of resources, type definitions, and implementations of those types. An assembly may also contain references to other assemblies. These resources, types and references are described in a block of data called a manifest. The manifest is part of the assembly, thus making the assembly self-describing.
An important aspect of assemblies is that they are part of the identity of a type. The identity of a type is the assembly that houses it combined with the type name. This means, for example, that if assembly A exports a type called T, and assembly B exports a type called T, the .NET runtime sees these as two completely different types. Furthermore, don't get confused between assemblies and namespaces - namespaces are merely a hierarchical way of organising type names. To the runtime, type names are type names, regardless of whether namespaces are used to organise the names. It's the assembly plus the typename (regardless of whether the type name belongs to a namespace) that uniquely indentifies a type to the runtime.
Assemblies are also important in .NET with respect to security - many of the security restrictions are enforced at the assembly boundary.

Web Services

2006-03-27T03:22:00.000-08:00

SQL

2006-03-27T02:21:00.000-08:00

***********************************************************************************

Deleting duplicate records in a table

select DISTINCT * into #temp from table1 --apply where condition

delete from table1

insert table1 select * from #temp

drop table #temp

table names starts with # will truncated and dropped after application end

***********************************************************************************

get day from date sql

datename("dw",getdate())

***********************************************************************************

select getdate()

To convert a given date to normal format

select convert(nvarchar(12),getdate(),103)

***********************************************************************************

To invoke a specified application at specified time

2006-03-26T20:35:00.000-08:00

This is the windows service which will invoke a application at 5.30 pm

Here I am invoking a web page

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.ServiceProcess;
using System.Timers;
using System.Configuration;
using System.Globalization;

namespace WinWin
{

public class WinService1 : System.ServiceProcess.ServiceBase
{

///

/// Required designer variable.
///

///
// private System.Timers.Timer aTimer;
private System.ComponentModel.Container components = null;
//private System.Timers.Timer aTimer = new System.Timers.Timer();
//private System.ComponentModel.Container components = null;

private System.Timers.Timer aTimer;
public WinService1()
{
//System.Timers.Timer aTimer;
// This call is required by the Windows.Forms Component Designer.
InitializeComponent();

// TODO: Add any initialization after the InitComponent call
}

// The main entry point for the process
//private System.Timers.Timer aTimer;
static void Main()
{
System.ServiceProcess.ServiceBase[] ServicesToRun;

// More than one user Service may run within the same process. To add
// another service to this process, change the following line to
// create a second service object. For example,
//
// ServicesToRun = new System.ServiceProcess.ServiceBase[] {new Service1(), new MySecondUserService()};
//

ServicesToRun = new System.ServiceProcess.ServiceBase[] { new WinService1() };

System.ServiceProcess.ServiceBase.Run(ServicesToRun);

}

///

/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
///

private void InitializeComponent()
{
//
// WinService1
//
this.ServiceName = "WinService1";

}

///

/// Clean up any resources being used.
///

protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
}

///

/// Set things in motion so your service can do its work.
///

///

private Timer timer;
protected override void OnStart(string[] args)
{

if (aTimer == null)
{
aTimer = new System.Timers.Timer();
aTimer.Elapsed +=
new ElapsedEventHandler(OnTimer);
//Let the timer trigger once a minute
aTimer.Interval = 59000;
aTimer.Enabled = true;
}
else
{
aTimer.Start();
}

/*

// TODO: Add code here to start your service.
DateTime currentSystemTime = DateTime.Now;

//System.Timers.Timer aTimer = new System.Timers.Timer();

// Hook up the Elapsed event for the timer.
//aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);

// Set the Interval to 2 seconds (2000 milliseconds).
//aTimer.Interval = 2000;
//aTimer.Enabled = true;

// TODO: Add code here to start your service.
int i = 1;
if(i == 1)
{
if(currentSystemTime.Hour == 18 & currentSystemTime.Minute == 0)
{
//Console.WriteLine ("In the Main");
//Console.WriteLine ("In the Main");
System.Diagnostics.Process proc = new System.Diagnostics.Process();
proc.EnableRaisingEvents=false;
proc.StartInfo.FileName="iexplore";
proc.StartInfo.Arguments="http://projectserver/lgnps.asp";
proc.Start();
//proc.WaitForExit();

}
else
{
}
}

*/

}

private void InitializeTimer()
{
if (timer == null)
{
timer = new Timer();
timer.AutoReset = true;
timer.Interval = 60000 * Convert.ToDouble(
ConfigurationSettings.AppSettings["IntervalMinutes"]);
timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
}
}

private void timer_Elapsed(object source,System.Timers.ElapsedEventArgs e)
{
RunCommands();
}

private void RunCommands()
{
// JobRunWebService.JobRunInterval objJob =
// new JobRunWebService.JobRunInterval();
// objJob.RunJob();
}

///

/// Stop this service.
///

protected override void OnStop()
{
if (aTimer != null) aTimer.Stop();
// TODO: Add code here to perform any tear-down necessary to stop your service.
}

public static void OnTimer(Object source,ElapsedEventArgs e)
{
RunDataLoader();
}
private static void RunDataLoader()
{
//Do your job in this procedure...
//while()

DateTime currentSystemTime = DateTime.Now;

//currentSystemTime.s
if(currentSystemTime.Hour == 17 & currentSystemTime.Minute == 30)
{
System.Diagnostics.Process proc = new System.Diagnostics.Process();
proc.EnableRaisingEvents=false;
proc.StartInfo.FileName="iexplore";
proc.StartInfo.Arguments="http://202.144.75.72/projectserver/lgnps.asp";
proc.Start();
}
}

protected override void OnPause()
{
if (aTimer != null) aTimer.Stop();
}
protected override void OnContinue()
{
if (aTimer != null) aTimer.Start();
}

}

}

Date Time

2006-03-24T04:25:00.000-08:00

set @date = convert(varchar(3), @Month) + '/1/' + convert(varchar(6), @Year)

while (Month(@Date) = @Month)
begin
set @HolidayDate = NULL
select @HolidayDate = HolidayDate from @Holiday where HolidayDate=@Date
select 'Date' as Element, convert(nvarchar(12),@date, 103) as [Date1], @date as [Date], DatePart(dw, @date) as [WeekDay], @DayNo as DayNo , @HolidayDate as HolidayDate
for xml raw

if( DatePart(dw, @date) != @wo1 and DatePart(dw, @date) != @wo2 and @HolidayDate is NULL) set @dayno = @dayno + 1
if(@dayno > 36) set @dayno = 1
set @date = dateadd(dd, 1, @date)

end

.net

2006-03-24T04:00:00.000-08:00

What is the .NET Framework?

The .NET Framework is a development and execution environment that allows different programming languages & libraries to work together seamlessly to create Windows-based applications that are easier to build, manage, deploy, and integrate with other networked systems.

For further details please visit

http://msdn.microsoft.com/netframework/gettingstarted/default.aspx