原生Ajax总结

function requestObject(){
            if(window.XMLHttpRequest){
                return new XMLHttpRequest();
            }else if{
                return new ActiveXObject('Mxsml2.XMLHTTP');
            }else{
                throw new Error("Could not create HTTP request object.");
            }
        }

request.send(null);

request.onreadystatechange=function(){
            if(request.readyState==4){
                console.log(request.status+":"+request.statusText);
            }
        }