ASP.NET AJAX is the foundation on which to build richer web applications that leverage the browser more fully but it doesn’t have the rich UI elements that really blur the distinction between web and desktop applications. With the Microsoft AJAX Library, you can apply familiar object-ori-ented design concepts and use the scripts across a variety of modern browsers. The ASP.NET 2.0 AJAX Extensions 1.0 include several powerful ASP.NET controls that make it easy to add AJAX functionality to an existing application or build better user experiences into a new application, but the AJAX Toolkit was developed to provide some rich ASP.NET AJAX controls that you can use to make your web applications really come to life. The Toolkit makes it easy to push the user interface of an application beyond what users expect from a web application.
The Toolkit is a shared source project with code contributions from developers from Microsoft and elsewhere. Most developers who download the AJAX Extensions should also download the Toolkit for the additional set of controls it contains. Information is available at http://ajax.asp.net/ajaxtoolkit. The CodePlex project mentioned by this page allows you to download a compiled dll with the controls and extenders, or you can download the source code and project files and compile it yourself. But either way, make sure you add the dll to your ToolBox in Visual Studio, as described in the documentation.
The Toolkit contains some new controls that have AJAX functionality and a lot of control exten-ders. The control extenders attach to another control to enhance or “extend” the control’s functionality. When you install the Toolkit, it creates a sample web application that has some samples of using the controls. Because the controls cover such a wide variety of application-development areas, they are presented here in three categories: page layout controls, user interface effects, and pop-ups. Within each category, the controls are listed alphabetically; the control names are self-explanatory, so you’ll find it easy to locate the information you need when using this chapter for later reference.
Also, note that the Toolkit project is ongoing and will continue to evolve as developers contribute to it. This chapter is up to date as of the time of this writing, but I expect that more will be added to the Toolkit regularly.