A.var url="operate=doCheckUserExists&uname="+uname; B.xmlHttpRequest=createXmlHttpRequest(); C.xmlHttpRequest.onreadystatechange=haoLeJiaoWo; D.xmlHttpRequest.open("POST",url,false);
A.util.Js B.engine.jsp C.dwr.Xml D.web.xm
A.XML B.DWR C.CSS D.JavaScript