function createxmlhttp()
{
    //create xmlhttp object   
    xmlhttpobj = false;
    try{
        xmlhttpobj = new XMLHttpRequest;
    }catch(e){
        try{
            xmlhttpobj=new ActiveXObject("MSXML2.XMLHTTP");
        }catch(e2){
            try{
                xmlhttpobj=new ActiveXObject("Microsoft.XMLHTTP");
            }catch(e3){
                xmlhttpobj = false;
            }
        }
    }
    return xmlhttpobj; 
}