Most of the power of AJAX resides on the client and is strictly related to the browser’s and platform’s client-side functionality. Even though a large share of AJAX pages are built using a slightly different set of server controls, they couldn’t work without a powerful environment available on the client and written in JavaScript. Such a script code governs the execution of out-of-band calls and often kicks in and replaces regular postbacks with AJAX postbacks. No AJAX functionality would ever be possible without JavaScript and a standard (and rich) Document Object Model (DOM). The DOM, though, is not enough.

The DOM represents the programming gateway to the page constituent elements, but it is not designed to provide programming facilities such as those you can find in a general-purpose library. Normally, the script tools you can leverage to consume objects and contents from the DOM are those provided by the JavaScript language. Not exactly a powerful toolkit. Enter the Microsoft AJAX Library.

The Microsoft AJAX library is written in JavaScript, although with a strong sense of objectorientation. The JavaScript language does support objects and allow the creation of custom objects. It does not, however, support full object-orientedness since it has no native concept of true object inheritance. Nonetheless, even excluding true object-orientation, JavaScript is still a modern and suitable language that can be used to build a class framework a la the .NET Framework. ASP.NET AJAX takes the JavaScript language to the next level by adding some type-system extensions and the notions of namespace and inheritance. In addition, the ASP.NET AJAX JavaScript supports interfaces and enumerations, and has a number of helper functions to manipulate strings and arrays.

These extensions are coded using the base set of instructions that characterize the core JavaScript language, and they’re persisted to the .js files that form the Microsoft AJAX client runtime environment.

Source of Information : Microsoft Press Introducing Microsoft ASP .NET AJAX


Subscribe to Developer Techno ?
Enter your email address:

Delivered by FeedBurner