现在对于一个项目中如何选用AJAX值得讨论

以下来自InfoQ和 Sitepoint的两篇文章的节选，前者讨论了JavaScript框架的选择标准，后者详细解释了Ext的优势。我想两个文章的节选片段已经为我们选择Ext作为表现层解决方案提供了足够的理由。

为什么选择Ext

Ext Comes to the Rescue

In a nutshell, Ext delivers just what we need -- a stable and uniform JavaScript platform for building rich web applications. Building on the Yahoo! UI Library, Ext has looked very promising for some time. When version 2.0 was released last week, however, the library matured into possibly the most robust JavaScript library available for developing rich web user interfaces.

There are a few alternatives out there of course, such as Dojo and the Yahoo! UI Library, but there are a few key points that, when combined, make Ext stand out from the crowd. These points include:

    * Ext is very fast. Performance is often a problem when programming JavaScript.
    * Ext is implemented in a 100% object-oriented, well structured, consistent way. This makes the library fast to learn, and the code easy to read and understand.
    * The modular implementation with its consistent base makes the library easy to extend.
    * All Ext elements (widgets) are ready for use. In contrast to many other libraries, the widgets are usable as they are, with pre-defined styles, settings, and behavior. Still, all elements are fully customizable and can be themed if required.
    * The Ext developers are extremely dedicated and competent, and have an understanding, and most importantly an interest, in users' needs. Ext documentation is thorough and full of working examples.
    * The Ext community is very active, and the tone is generally very positive.
    * Ext can be used both under a free and a commercial license.
    * Last but not least, Ext looks very slick!

Some (or maybe even all) of this is true for other libraries as well. I don't pretend to suggest that there aren't other excellent alternatives out there, and you should investigate all options before deciding to stick with one. However, in my experience Ext gives the best overall impression, which is why I decided to run with it.