Beginning ASP.NET 4: in C# and VB

Chapter 10. ASP.NET AJAX

WHAT YOU WILL LEARN IN THIS CHAPTER:

• Using the UpdatePanel control to avoid page flicker

• Understanding the ScriptManager control that enables the Ajax functionality

• Using the UpdateProgress control to notify users about progress of an Ajax operation

• Creating web services and page methods that are accessible by your client-side script

• Using the client-side ASP.NET AJAX Library

Over the past few years, Ajax has popularized itself immensely in the web development community. Although the technology that drives Ajax has been around for quite some time, it wasn't until the beginning of 2005 that it got an official name. Ajax, which stands for Asynchronous JavaScript And XML, enables your client-side web pages to exchange data with the server through asynchronous calls. Probably the most popular feature driven by Ajax is the flicker-free page that enables you to perform a postback to the server without refreshing the entire page.

To enhance your web site with Ajax features you can choose among different Ajax frameworks, each offering a set of features and tools including a client-side JavaScript framework to enable Ajax in the browser and at the server. Although a number of different Ajax frameworks are available for ASP.NET, the most obvious one is Microsoft ASP.NET AJAX, because it comes fully integrated with the .NET 4 Framework and Visual Web Developer 2010. The cool thing about ASP.NET AJAX is that it has great interoperability with other client-side frameworks (including ...