Baidu Musicbox 用到的ajax代码

  }
        if (!http_request){
            alert(''Giving up :( Cannot create an XMLHTTP instance'');
            return false;
        }
        http_request.onreadystatechange=handleStateChange;    
        http_request.open(bmethod,burl,true);
        if(Formdata){
            http_request.setRequestHeader("Content-Length",Formdata.length);   
            http_request.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
            http_request.send(Formdata);
        }else{
            http_request.setRequestHeader("Content-Type","text/html");
            http_request.send(null);
        }
    }
    function handleStateChange(){
        if(http_request.readyState==4 && http_request.status==200){
            var response_content;
            if(bXML){
                response_content=http_request.responseXML;
            }else{
                response_content=http_request.responseText;    
            }        
            if(typeof rdRandleResponse == "function"){
                rdRandleResponse(response_content, attach);
            }else{
                eval(rdRandleResponse+"(response_content,attach)");
            }
        }
    }
    doHttpRequest();
}

function