<!DOCTYPE?html>
<html>
<head>
???<meta?charset="UTF-8">
???<title></title>
</head>
<body>
<div>
???<input?type="button"?id="btn3"?value="按鈕3">
</div>
<script>
???function?showMsg(){
???????alert('Hello?world!');
???}
???//browser?compatible
var?eventUtil={
???????//add?handler
addHandler:function(element,type,handler){
???????????if(element.addEventListener){
???????????????//dom2?level
element.addEventListener(type,handler,false);
???????????}else?if(element.attachEvent){
???????????????//ie
element.attachEvent('on'+type,handler);
???????????}else{
???????????????//dom0?level
???????????????//在js中所有用.連接屬性的時(shí)候都可以用[]，element.onclick?===?element['onclick']
element['on'+type]?=?handler;
???????????}
???????},
???????//remove?handler
removeHandler:function(element,type,handler){
???????????if(element.removeEventListener){
???????????????element.removeEventListener(type,handler,false);
???????????}else?if(element.detachEvent){
???????????????element.detachEvent('on'+type,handler);
???????????}else{
???????????????element['on'+type]?=?null;
???????????}
???????}
???};
???//call?object
eventUtil.addHandler('btn3','click',showMsg);
???//eventUtil.removeHandler('btn3','click',showMsg);
</script>
</body>
</html>
2015-01-12
43行應(yīng)該改為：eventUtil.addHandler(btn3,'click',showMsg);