<script type="text/javascript">    function EventUtil() {        var _self = this;        ///添加事件        var addEvent = (function () {            if (document.addEventListener) {                return function (el, type, fn) {                    el.addEventListener(type, fn, false);                }            } else {                return function (el, type, fn) {                    el.attachEvent("on" + type, function () {                        return fn.call(el, window.event);                    });                }            }        })();        ///添加属性改变事件        var addPropertyChangeEvent = function (obj, fn) {            if (window.ActiveXObject) {                obj.onpropertychange = fn;            } else {                obj.addEventListener("input", fn, false);            }        }        //移除事件        var removeEvent = function (obj, type, fn) {            if (obj.removeEventListener) {                obj.removeEventListener(type, fn, false);            } else if (obj.detachEvent) {                obj.detachEvent("on" + type, obj["on" + type + fn]);                obj["on" + type + fn] = null;            }        }        //加载事件        var loadEvent = function (fn) {            var oldonload = window.onload;            if (typeof oldonload != "function") {                window.onload = fn;            } else {                window.onload = function () {                    oldonload();                    fn();                }            }        }        //阻止事件        var stopEvent = function (e) {            e = e || window.event;            if (e.preventDefault) {                e.preventDefault();                e.stopPropagation();            } else {                e.returnValue = false;                e.cancelBubble = true;            }        }        //如果仅仅是阻止事件冒泡        var stopPropagation = function (e) {            e = e || window.event;            if (!+"\v1") {                e.cancelBubble = true;            } else {                e.stopPropagation();            }        }        //取得事件源对象        var getEvent1 = function (e) {            e = e || window.event;            var obj = e.srcElement ? e.srcElement : e.target;            return obj;        }        //取得事件源对象        var getEvent2 = function (e) {            if (window.event) return window.event;            var c = getEvent2.caller;            while (c.caller) {                c = c.caller;            }            return c.arguments[0];        }        //或者这个功能更强大        var getEvent3 = function (e) {            var e = e || window.event;            if (!e) {                var c = this.getEvent3.caller;                while (c) {                    e = c.arguments[0];                    if (e && (Event == e.constructor || MouseEvent == e.constructor)) {                        break;                    }                    c = c.caller;                }            }            var target = e.srcElement ? e.srcElement : e.target,                    currentN = target.nodeName.toLowerCase(),                    parentN = target.parentNode.nodeName.toLowerCase(),                    grandN = target.parentNode.parentNode.nodeName.toLowerCase();            return [e, target, currentN, parentN, grandN];        }        _self.addEvent = addEvent;        _self.addPropertyChangeEvent = addPropertyChangeEvent;        _self.removeEvent = removeEvent;        _self.loadEvent = loadEvent;        _self.stopEvent = stopEvent;        _self.stopPropagation = stopPropagation;        _self.getEvent1 = getEvent1;        _self.getEvent2 = getEvent2;        _self.getEvent3 = getEvent3;    }    var eventUtil = new EventUtil();    eventUtil.loadEvent(function () {        eventUtil.addEvent(document, "click", function (e) {            alert(eventUtil.getEvent3(e));        });        eventUtil.addPropertyChangeEvent(document,function(e){            alert(eventUtil.getEvent3(e));        });    });</script>