js中使用Ajax方法

// 请求服务器
//
// @param url
// 请求服务的地址
// @param param
// 要处理的参数
function Core_Ajax_Text(url, param) {
var http_request = false;
// 开始初始化XMLHttpRequest对象
if (window.XMLHttpRequest) { // Mozilla 浏览器
http_request = new XMLHttpRequest();
if (http_request.overrideMimeType) {// 设置MiME类别
http_request.overrideMimeType("text/xml");
}
} else if (window.ActiveXObject) { // IE浏览器
try {
http_request = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
try {
http_request = new ActiveXObject("Microsoft.XMLHTTP");
} catch (e) {
}
}
}
if (!http_request) { // 异常，创建对象实例失败
window.alert("不能创建XMLHttpRequest对象实例.");
return false;
}
http_request.open("POST", url, false);
http_request.setRequestHeader("Content-Type",
"application/x-www-form-urlencoded;charset=UTF-8");
http_request.setRequestHeader("Cache-Control", "no-cache");
http_request.setRequestHeader("If-Modified-Since", 0);
http_request.send(param);
var reValue = http_request.responseText.replace(/(^\s*)|(\s*$)/g, "");
return reValue;
}