ASP.Net AJAX is Microsoft's free framework for developing rich internet applications (RIA) that work across all browsers. It includes four components: Server-Side ASP.NET AJAX, Client-Side ASP.NET AJAX, the AJAX Control Toolkit and the jQuery library.

The AJAX Control Toolkit that has just been updated with some new functionality. Let's have a look.

A Framework Overview

Let's step back and look at the four components of the ASP.NET AJAX framework:

  • Server-Side ASP.NET AJAX: Included as a standard in the .NET framework 3.5, this programming model enables developers to add AJAX functionality to a web application without writing Javascript.
  • Client-Side ASP.NET AJAX: For those who love their Javascript and want to build client-side RIAs, then there's the Client-Side library. Also included with the .NET framework 3.5, they are currently working on a new version.
  • AJAX Control Toolkit: The AJAX Control Toolkit contains over 30 different controls to use when developing RIAs and you don't need to know Javascript to use them.
  • jQuery Library: An open source Javascript Library, a standard component of ASP.NET MVC apps.

AJAX Control Toolkit Updates

The AJAX Control Toolkit is an open source project, worked on jointly by Microsoft and the ASP.NET AJAX Community. The toolkit is an infrastructure that helps developers to create extenders and controls that can be reused, customized and extended as needed. It also includes a number of out of the box controls ready and waiting to be implemented.

So what's new in Version 3.0.30512?


A new WYSIWYG HTML Editor that also allows you to view source and preview your content -- like most HTML Editors.


HTMLEditor Control

You can get both a client-side HTML editor and a server side version. In addition you can change the buttons on the top toolbar and remove the bottom toolbar (taking away the ability to view source or preview).

Add the ability to create a custom skin to the editor and insert the editor inside TABS and you've got a pretty functional control there.


HTMLEditor - tabs

The HTMLEditor was built by a company called Obout.


The ComboBox is the combination of a textbox and the ability to select an option from a dropdown list.



It has a number of similar properties, behaviors and naming conventions as the Windows Forms ComboBox. The ComboBox is a supplement to the AutoCompleteExtender. It can bind to data source controls, can restrict input to what is in the list, has both text and value properties and more.

Using the CssClass property you can create a custom theme for the ComboBox.


The ColorPicker is an extender. It can be added to any textbox to enable users to select a color and get the associated color code. A client-side pop up control opens to show a number of colors to select from.


ColorPicker Default

You just click inside the textbox to have the colors UI pop up. You can also add a SampleControl and a Popup Button control, shown below, to make your ColorPicker a bit more functional.



Theming is not currently supported, but is expected using the CssClass Property. In the meantime you can override a predefined set of CSS classes if you want.

Developing RIAs

The AJAX Control Toolkit is supposed to be cross-browser compliant. These screenshots were taken with FireFox 3, so it does appear to work there. And of course it's going to work with Internet Explorer.

Both Visual Studio and the free Visual Web Developer Express 2008 support developing AJAX applications, including Intellisense for Javascript and other Javascript libraries like jQuery and application debugging.

You can download the latest version of the AJAX Control Toolkit on CodePlex.