JS事件相关概念和操作

1.事件流

2.跨浏览器事件处理

var EventUtil = {
            // 添加事件监听
            addEvent : function (element, type, handler) {
                if (element.addEventListener)
                {
                    element.addEventListener(type, handler, false);
                } else if (element.attachEvent)
                {
                    element.attachEvent("on" + type, handler);
                }
            },
            // 解除事件监听
            delEvent : function (element, type, handler) {
                if (element.removeEventListener)
                {
                    element.removeEventListener(type, handler, false);
                } else if (element.detachEvent)
                {
                    element.detachEvent("on" + type, handler);
                }
            }
        }

3.获取事件对象

var EventUtil = {
        // 获取event对象
        getEvent : function (event) {
            return event ? event : window.event;
        },
        // 获取事件源
        getTarget : function (event) {
            return  event.target || event.srcElement;
        },、
        // 阻止默认行为
        stopDefault : function (event) {
            if (event.preventDefault)
            { 
                event.preventDefault();
            } else {
                event.returnValue = false;
            }
        },
        // 阻止冒泡
        stopBubble : function (event) {
            if (event.stopPropagation)
            {
                event.stopPropagation();
            } else {
                event.cancelBubble = true;
            }
        }
    }