ASP.NET AJAX - Microsoft Ajax Library

Microsoft Ajax Library

The Microsoft Ajax Library is a JavaScript library that provides the features for the client portion of the ASP.NET AJAX framework.

• Components – The library provides an infrastructure to build either visual or non-visual JavaScript components. A global JavaScript object – Sys.Application – is responsible for managing the lifecycle of client components.
• JavaScript extensions – An enhanced type system is introduced to emulate object-oriented constructs such as namespaces, classes and interfaces; and to perform reflection on client types.
• Abstraction API – Common operations on the DOM (retrieving elements, setting styles and other manipulations) are automatically translated by the library into browser-specific calls.
• Ajax – A set of client components is provided to handle Ajax requests and web-service calls.
• Application Services – The library allows accessing the ASP.NET Membership, Authentication, Roles and Profile services from the client side.

Recently, new features have been announced as part of the ASP.NET AJAX 4.0 release:

• Template Engine – Allows displaying data on the client side by using HTML templates and a custom binding notation. This approach avoids performing page rendering on the server side.
• Declarative instantiation of client components – Allows registration, instantiation and configuration of client components using markup code, without writing any imperative JavaScript code.
• Live Bindings – Synchronize element properties.