var list = document.getElementById("myList"); EventUtil.addHandler(list,"click",function(event){ event = EventUtil.getEvent(event); var target = EventUtil.getTarget(event); switch(target.id){ case"doSomething": document.title = "I change the document's title"; break; case"goSomewhere": loaction. break; case"sayHi": alert("Hello World!!!"); break; } })對於事件委託這一塊一直不是很理解，說是用到了事件冒泡，但是事件委託綁定的不是dom樹種最高層次上添加處理程序，怎麼事件冒泡的它的子元素,求大佬解答