Programming ASP.NET AJAX

Chapter 14. Client Controls

This chapter covers client-side controls that ship with the ASP.NET AJAX Futures. These controls mimic the behavior of ASP.NET web controls and allow for consistent development on both the server and the client. In addition, they support convenient features, such as data binding, which you’ll explore in Chapter 16.

Introducing ASP.NET AJAX Client Controls

The core release of ASP.NET AJAX 1.0 does not include purely client-based controls. However, these controls are found in the Futures release and are implemented in the Sys.Preview.UI namespace. Sys.Preview.UI is the client-side equivalent of the similarly named and well-known Web.UI namespace in ASP.NET.

Tip

In pre-release versions of ASP.NET AJAX, the client-side namespace was named Web.UI and Sys.UI.

Sys.Preview.UI contains a large number of ASP.NET AJAX HTML controls and web controls. The functionality of ASP.NET AJAX controls is similar but not identical to that of ASP.NET server controls. They provide a consistent, browser-independent model that enables JavaScript code to access and change client control properties. This would require considerable knowledge of JavaScript if attempted using controls outside theASP.NET AJAX framework. It would also take quite a knack for scripting workarounds to account for browser inconsistencies.

Table 14-1 lists controls available in the Futures release. The table lists the HTML elements with which the ASP.NET AJAX control works, along with the equivalent JavaScript ...