第一次亲密接触Ajax

Ajax 框架
var http_request = false;
function send_request(url) {
http_request = false;
if(window.XMLHttpRequest) {
http_request = new XMLHttpRequest();
if (http_request.overrideMimeType) {
http_request.overrideMimeType("text/xml");
}
}
else if (window.ActiveXObject) {
try {
http_request = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
try {
http_request = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {}
}
}
if (!http_request) {
window.alert("不能创建XMLHttpRequest 对象实例.");
return false;
}

http_request.onreadystatechange = processFunction;

http_request.open("GET", url, false);
http_request.send(null);
}

function processFunction()
{
if (http_request.readyState == 4) {
if (http_request.status == 200) {
var ResponseText = http_request.responseText;
//var ResponseXml = http_request.responseXml;

// 处理返回对象
}
else
{
alert("您所请求的页面有异常。");
}
}
}

调用方法：
send_request(url);
例如：
send_request('process.asp?id=1&name=2');