AJAX

function Ajax(obj) {
    var instance = new Object();
    //instance.XMLHttpReq;
    instance.url = obj.url;
    instance.backFunction = obj.callback;
    instance.cache = obj.cache == undefined ? false : obj.cache; //默认缓存为false
    // 创建XMLHttpRequest对象
    createXMLHttpRequest = function() {
        if (window.XMLHttpRequest) {//Mozilla浏览器
            instance.XMLHttpReq = new XMLHttpRequest();
        }
        else if (window.ActiveXObject) {
            try {
                instance.XMLHttpReq = new ActiveXObject("Msxml2.XMLHTTP");
            } catch (e) {
                try {
                    instance.XMLHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
                } catch (e) { }
            }
        }
    };
    // 发送请求函数
    sendRequest = function(url) {
        this.createXMLHttpRequest();
        //if (!instance.cache) {
            //instance.XMLHttpReq.setRequestHeader("If-Modified-Since", "0");
        // }
        // 发送请求
        instance.XMLHttpReq.open("GET", url, true);
        instance.XMLHttpReq.onreadystatechange = this.processResponse; //指定响应函数    
        instance.XMLHttpReq.send(null);
    };
    //处理响应函数
    processResponse = function() {
        if (instance.XMLHttpReq.readyState == 4) {//判断对象状态
            if (instance.XMLHttpReq.status == 200) {// 信息已经成功返回，开始处理信息
                instance.backFunction(instance.XMLHttpReq.responseText);
                instance = null;
            } else {
                //alert("您所请求的页面有异常");
                instance = null;
            }
        }
    };
    sendRequest(instance.url);

}

function checkLogin() {
            var uname = JsCore.$$("uname").value;
            var upass = JsCore.$$("upass").value;
            Ajax({
                url: "/class/checkvcode.aspx?vcode=1&uname=" + uname + "&upass=" + upass + "&num=" + Math.random(), callback: function (data) {
                    if (data != "") {
                        if (data == "3") {
                            location.href = "/member/default.aspx";
                        }
                        if (data == "1") {
                            //alert(‘用户名或密码输入错误！‘);
                            JsCore.$$("uname_msg").style.display = "block";
                            JsCore.$$("upass_msg").style.display = "block";
                        }
                    }
                }
            });
        }