说明：  The solution to building applications with fast, user-friendly, and responsive user interfaces is here. Yes! Ajax is in. Ajax is an acronym for Asynchronous JavaScript and XML—a technology that can reduce web page postbacks significantly and yield better response times for your web applications. Using Ajax, the hits to the web server are reduced—thus, you have fewer page refreshes. Moreover, you can use Ajax to ensure that a specific portion of the page is refreshed and not the entire page content.(Source Code)