简易ajax封装

gistfile1.js

var myAjax = {
    // XMLHttpRequest IE7+, Firefox, Chrome, Opera, Safari ；  ActiveXObject IE6, IE5
    xhr: window.XMLHttpRequest ? new XMLHttpRequest() : new ActiveXObject('Microsoft.XMLHTTP'),
    get: function (url, callback) {
        this.xhr.open('get', url);
        this.onreadystatechange(callback, this.xhr);
        this.xhr.send(null);        
    },
    post: function (url, data, callback) {
        this.xhr.open('post', url);
        this.xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');
        this.onreadystatechange(callback, this.xhr);
        this.xhr.send(data);
    },
    onreadystatechange: function (func, _xhr) {
        _xhr.onreadystatechange = function () {
            if (_xhr.readyState == 4) {
                if (_xhr.status == 200) {
                    func(_xhr.responseText);
                }
            }
        }
    }
}

//usaege：

$('#btn_nowTime1').bind('click', null
    , function () {
        myAjax.post('AjaxHandler.ashx', 'func=GetServerTime'
            , function (data) {
                if (data)
                    alert(data);
            }
        );
    });