1. Tab Key in ASP.NET

Why does the compiler say that 'Linq' does not exist in the 'System' namespace when specifying a using statement as follows:

using System.Linq;

Answer : Add System.Core reference ( version 3.5 )

1. Events in ASP.NET Master and Content Pages

On your Loging Page Page_Load event use:

if (Request.QueryString["logout"] == "true")

{

    string nextpage = "Login.aspx";

    Response.Write("<SCRIPT LANGUAGE=javascript>");

    Response.Write("{");

    Response.Write(" var Backlen=history.length;");

    Response.Write(" history.go(-Backlen);");

    Response.Write(" window.location.href='" + nextpage + "'; ");

    Response.Write("}");

    Response.Write("</SCRIPT>");

}

On your Logout page Page_Load use the following :

Session.Abandon();

FormsAuthentication.SignOut();

Response.Redirect("Login.aspx?logout=true");

Life should be good after that.

1. How-to use ClientIDs in JavaScript without the ugliness
2. Focus in ASP.NET Controls
3. Adding Client-Side Confirmation when Deleting
4. Pack and minimize your JavaScript code size
5. How to detect IE8 using JavaScript (Client side)
6. JSAN
7. 25 Open Source JavaScript Libraries And Frameworks - Vote For Your Favorite
8. Localizing client side JavaScriptLocalizing client side JavaScript
9. Overriding javascript in webresource.axd
10. Combine, minify and compress JavaScript files to load ASP.NET pages faster
11. Minify your Javascripts!
12. Make your pages load faster by combining and compressing javascript and css files
13. Downloading JavaScript Files in Parallel

    var sPath = window.location.pathname;
    var sPage = sPath.substring(sPath.lastIndexOf('/') + 1);
    alert(sPage);
    alert(sPath);

    Source Link

    Source 2  

1. Nice Titles revised
2. 40+ Tooltips Scripts With AJAX, JavaScript & CSS 
3. Pure CSS Tooltips
4. DHTML Goodies
5. Advanced Tooltip Control - ASP.NET AJAX
6. ASP.NET Tooltip control 
7. Tooltip a DIV through DOM/Javascript

1) Use the Global Application_Error for Global.asax to monitor hidden errors.

2) Use the Web Developer Utility

private int IsIntegerInCSharp(string intString)

{

    int intReturn;

    if (!Int32.TryParse(intString, out intReturn))

    {

        throw new Exception("Invalid integer");

    }

    return intReturn;

}

1. Implement ASP.NET AJAX with the UpdatePanel control
2. Creating a Simple ASP.NET Page with Multiple UpdatePanel Controls
3. UpdatePanel Tips and Tricks
4. ScriptManager Enables AJAX In Your Web Apps
5. Drag and Drop with ASP.NET AJAX
6. New AJAX Support For Data-Driven Web Apps
7. AJAX Application Architecture, Part 1
8. AJAX application architecture, Part 2
9. Managing the User Experience in AJAX
10. Lazy Loading the ASP.NET AJAX TabContainer Control 
11. More Sample AjaxControlToolkit TabContainer Themes
12. ASP.NET AJAX TabContainer – Tips and Tricks 
13. How To: Lazy-load TabPanel's within the AjaxControlToolkit's TabContainer Control
14. Delay Load an UpdatePanel
15. Customize Controls with AJAX Extenders
16. Modal Dialog Boxes with AJAX
17. Drag and Drop with ASP.NET AJAX
18. Creating Sophisticated Animations with the Microsoft AJAX Library
19. ASP.NET AJAX Extender for multicolumn drag and drop
20. The Ever-Useful $get and $find ASP.NET AJAX Shortcut Functions
21. Documentation for: ASP.NET Ajax Version Ajax 1.0,  MSDN1 & MSDN2
22. Delayed Content Loading Using the AJAX.NET Timer and UpdatePanel
    
23. ASP.NET/ AJAX Page Loader Progress Bar/ Splash Screen