The new ASP.NET Ajax Library (Beta) is an open source, JavaScript, library that enables you to build database-driven Ajax applications that execute entirely within the web browser. The library includes all of the Ajax controls included in the AJAX Control Toolkit. The library works with ASP.NET Web Forms, ASP.NET MVC, and even pure HTML applications.

Start using the ASP.NET Ajax Library (Beta)

The ASP.NET Ajax Library includes a new version of the AJAX Control Toolkit designed to be used from both server and client code. If you are interested by the original version of the AJAX Control Toolkit then you can still download it from the AJAX Control Toolkit project on CodePlex.

Download the Original AJAX Control Toolkit

The Microsoft Ajax content delivery network (CDN) enables you to easily add ASP.NET Ajax Library and jQuery scripts to your Web applications. You can start using the ASP.NET Ajax Library or jQuery simply by adding a <script> tag to your page that points to Ajax.microsoft.com.</p>

By taking advantage of the Microsoft Ajax CDN, you can significantly improve the performance of your Ajax applications. The contents of the Microsoft Ajax CDN are cached on servers located around the world. In addition, the Microsoft Ajax CDN enables browsers to reuse cached JavaScript files for Web sites that are located in different domains.

View instructions for using the Microsoft Ajax CDN.

Developers familiar with the ASP.NET server-side programming model can take advantage of the ASP.NET AJAX server-side controls such as the ScriptManager, UpdatePanel, and the UpdateProgress control to add AJAX functionality to an ASP.NET application without writing any JavaScript. For example, the UpdatePanel control enables you to update a portion of an ASP.NET page without requiring you to reload the entire page. The ScriptManager control enables you to manage browser history in an AJAX application by updating the browser back button after an AJAX request.

The ASP.NET AJAX server-side controls are included as a standard part of the ASP.NET 3.5 framework. These controls are already in your Visual Studio/Visual Web Developer toolbox. If you are using an earlier version of the ASP.NET framework, such as ASP.NET 2.0, then you can download the ASP.NET AJAX Extensions.

In addition the AJAX Control Toolkit (described below) provides many more controls that you can add to your toolbox and include in your pages.

Learn more about server-side ASP.NET AJAX by watching a video tutorial or reading a written tutorial.

The AJAX Control Toolkit is included in the ASP.NET Ajax Library. The Ajax Library contains more than 30 controls that enable you to easily create rich, interactive web pages. For example, you can use the Ajax Library controls to display HTML editors, auto-complete textboxes, cascading dropdown lists, picture slide shows, and modal popup dialog boxes.

You don't need to know JavaScript to use the controls in the ASP.NET Ajax Library. For example, if you want to add a popup calendar to a TextBox control, you can simply select the Add Extender task option and select the Toolkit Calendar from a dialog box.

You also can use most of the controls from the ASP.NET Ajax Library in ASP.NET MVC and even pure HTML web applications.

The ASP.NET Ajax Library is currently being released as Beta software. You can download the ASP.NET Ajax Library from the http://Ajax.CodePlex.com website.

If you prefer, you can download the original AJAX Control Toolkit.

The jQuery library is a very popular open source JavaScript library that has a passionate and active developer community. jQuery enables you to easily retrieve and manipulate elements from a HTML document by using a selector syntax similar to the syntax used in Cascading Style Sheets. The jQuery library is included as a standard part of Microsoft ASP.NET MVC applications.

Visual Studio 2008 and the free Visual Web Developer Express 2008 provide you with a great development environment for creating AJAX applications. Visual Studio supports Intellisense for JavaScript, and popular JavaScript libraries such as jQuery, so that you get JavaScript statement completion as you type.

Visual Studio and Visual Web Developer also support rich debugging of executing JavaScript applications. You can set breakpoints, inspect objects, and use the immediate window to modify JavaScript at runtime.

Download Visual Web Developer Express from this website and start building rich AJAX applications.