Ajax简单请求示例

请把此代码保存为 ajax.htm 放在IIS服务器里运行!

xmlHttp;
function createXMLHttpRequest(){
if(window.ActiveXObject){
xmlHttp = new ActiveXObject();

}
else if(window.XMLHttpRequest){
xmlHttp = new XMLHttpRequest();
}
}
function startRequest(){
createXMLHttpRequest();
xmlHttp.onreadystatechange = handleStateChange ;
xmlHttp.open(,,true);
xmlHttp.send(null);
}
function handleStateChange(){
if(xmlHttp.readyState== ){
if(xmlHttp.status == ){
alert(+xmlHttp.responseText);
}
}

}