XMLHttpRequest=function(){

try{

returnnewActiveXObject("Msxml2.XMLHTTP.6.0");

}catch(e){}

try{

returnnewActiveXObject("Msxml2.XMLHTTP.3.0");

}catch(e){}

try{

returnnewActiveXObject("Msxml2.XMLHTTP");

}catch(e){}

try{//老版本的InternetExplorer(IE5和IE6)

returnnewActiveXObject("Microsoft.XMLHTTP");

}catch(e){}

returnfalse;

}

}

returnnewXMLHttpRequest();

}

varxhr=getHttpObject();

xhr.onreadystatechange=function(){