Packaging

The packaging of ASP.NET 2.0 AJAX can be fairly confusing. The basics of the packaging are:

• ASP.NET 2.0 AJAX Extensions 1.0—The ASP.NET 2.0 AJAX Extensions 1.0, also referred to as the RTM/Core code, is an independent download. This contains the functionality that will receive support from Microsoft in the initial release of the product. The source code is available.
• ASP.NET AJAX Futures Community Technology Preview (CTP) — The ASP.NET 2.0 AJAX framework contains a set of functionality that is experimental in nature. This functionality will eventually become integrated with the RTM/Core code. During the initial release, the Futures CTP functionality will be a separate download from the RTM/Core bits. This will not receive specific support from Microsoft beyond community-based support. The CTP bits require that the RTM/Core bits already be installed for the CTP bits to be installed. The CTP is also referred to as Value-Added Bits.
• Microsoft AJAX Library—The Microsoft AJAX Library is a set of JavaScript client libraries that make up the standard download to a web browser and provide much of the support for AJAX in the client. These libraries will work with a non-IIS server and are available as a separate download. This library is included in the ASP.NET 2.0 AJAX Extensions 1.0 download as well as being available as a separate download.
• ASP.NET AJAX Control Toolkit — The AJAX Control Toolkit is a separate download that provides a set of client-side GUI widgets that integrate with the ASP.NET 2.0 AJAX framework. The toolkit is licensed separately from the framework and includes the source code for developers who would like to review the source.

Futures

It has already been announced that ASP.NET 2.0 AJAX will be integrated into the .NET framework and Visual Studio in the Orcas versions of these products. Future versions will undoubtedly have more integration between ASP.NET 2.0 AJAX, ASP.NET, and Visual Studio.

Summary

AJAX provides developers a foundation to build web-based applications with an improved user experience. In this introductory chapter, you have looked at the following:

• Development from a historical perspective
• Web development methodologies
• Some of the features that ASP.NET AJAX provides, such as improved user responsiveness and decreased load on the web server
• Multiple technologies that can improve the user experience
• The general components in the ASP.NET 2.0 AJAX packaging
• The problems ASP.NET AJAX solves, and who is using it

Understanding AJAX

• AJAX is an acronym for Asynchronous JavaScript and XML. If you think it doesn't say much, we agree. Simply put, AJAX can be read "empowered JavaScript", because it essentially offers a technique for client-side JavaScript to make background server calls and retrieve additional data as needed, updating certain portions of the page without causing full page reloads. Figure 1.4 offers a visual representation of what happens when a typical AJAX-enabled web page is requested by a visitor