JavaScript跨浏览器事件处理

var EventUtil = {
    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;
        }
    },
    stopPropagation:function(event){
        if(event.stopPropagation){
            event.stopPropagation();
    }
        else{
            event.cancelBubble = true;
    }
};