Ajax开发框架+用户名检测实例(调试通过)
<script language="javascript">var http_request=false;function send_request(url){//初始化,指定处理函数，发送请求的函数http_request=false;//开始初始化XMLHttpRequest对象if(window.XMLHttpRequest){//Mozilla浏览器http_request=new XMLHttpRequest();if(http_request.overrideMimeType){//设置MIME类型http_request.overrideMimeType("text/html");}}else if(window.ActiveXObject){//IE浏览器try{http_request=new ActiveXObject("Xsxml2.XMLHTTP");}catch(e){try{http_request=new ActiveXObject("Microsoft.XMLHTTP");}catch(e){}}}