跨平臺出不來
<%@ page language="java" contentType="text/html; charset=utf-8"
? ? pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Insert title here</title>
<script type="text/javascript">
function showmes(){
alert("跨平臺事件處理");
}
var but3=document.getElementById("but3");
? var eventutil={
addHandler: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;
}
},
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;
}
}
}
eventutil.addHandler(but3,'click',showmes);
</script>
</head>
<body>
<input type="button" value="按鈕3" id="but3">
</body>
</html>
2016-05-02
因為講師把script放到body最后了 ， 你的代碼先運行的javascript的 所以后面的html沒有對象?
2016-05-02
缺少window.onload=function(){}，加到文檔head中再試試。