function createRequestObject(){
    var req;
    try{
        req=new XMLHttpRequest();
    }catch(e){
        try{
            req=new ActiveXObject("Msxml2.XMLHTTP");
        }catch(e){
            try{
                req=new ActiveXObject("Microsoft.XMLHTTP");
            }catch(e){
                return false;
            }
        }
    }
    return req;
}