我这段代码的回调函数哪出错,请各位大神指教
function req(){
createRequest();
var zipcode=document.getElementById("zipcode").value;
var url="b.jsp?zipcode=" + escape(zipcode);
request.open("POST",url,true);
request.onreadystatechage=updatePage;
request.send(null);
}
function updatePage(){
if(request.readyState==4){
alert("readyState is done");
if(request.status==200){
//alert("service is done");
var response=request.responseText.split(",");
document.getElementById("city").value=response[0];
document.getElementById("province").value=response[1];
}
}
}