Dom兼容性

var EventUtil = {
    //根据情况分别使用dom2 || IE || dom0方式 来添加事件
    addHander: function (element, type, handler) {
        if (element.addEventListener) {
            element.addEventListener(type, handler, false);
        } else if (element.attachEvent) {
            element.attachEvent('on' + type, handler);
        } else {
            element['on' + type] = handler;
        }
    },
    //根据情况分别获取DOM或者IE中的事件对象，事件目标，阻止事件的默认行为
    getEvent: function (event) {
        return event ? event : window.event;
    },
    getTarget: function (event) {
        return event.target || event.srcElement;
    },
    preventDefault: function (event) {
        if (event.preventDefault) {
            event.preventDefault();
        } else {
            event.returnValue = false;
        }
    },
    //根据情况分别取消DOM或者IE中事件冒泡
    stopPropagation: function (event) {
        if (event.stopPropagation) {
            event.stopPropagation();
        } else {
            event.cancelBubble = false;
        }
    }
}