小弟碰到一个棘手的问题，下面的代码用两个方式添加事件，但是不管怎么添加，按钮的onclick只会触发一次，第二次点击的时候就没有反应了，帮忙看一下<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>javascript事件</title>
</head>
<body>
<input type="button" id="btn3" value="按钮3" />
<br />
</body>
<script type="text/javascript">
var btn3 = document.getElementById("btn3");
btn3.onclick = function(){
document.body.innerHTML += "btn3 clicked! <br />";
}
if(document.all){
btn3.attachEvent("onclick",function(){document.body.innerHTML += "btn3 clicked! <br />";})
} else {
btn3.addEventListener("click",function(){document.body.innerHTML += "btn3 clicked! <br />"},true);
}
</script>
</html>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>javascript事件</title>
</head>
<body>
<input type="button" id="btn3" value="按钮3" />
<br />
</body>
<script type="text/javascript">
var btn3 = document.getElementById("btn3");
btn3.onclick = function(){
document.body.innerHTML += "btn3 clicked! <br />";
}
if(document.all){
btn3.attachEvent("onclick",function(){document.body.innerHTML += "btn3 clicked! <br />";})
} else {
btn3.addEventListener("click",function(){document.body.innerHTML += "btn3 clicked! <br />"},true);
}
</script>
</html>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
<title>javascript事件</title>
</head>
<body>
<input type="button" id="btn3" value="按钮3" />
<br />
</body>
<script type="text/javascript">
var btn3 = document.getElementById("btn3");
btn3.onclick = function(){
//document.body.innerHTML是重新加载html，一些动态绑定的事件或样式都失效了
//document.body.innerHTML += "btn3 clicked! <br />";
document.body.appendChild(document.createTextNode("btn3 clicked! "));
document.body.appendChild(document.createElement("<br />"));
}
//if(document.all){
// btn3.attachEvent("onclick",function(){document.body.innerHTML += "btn3 clicked! <br />";})
//} else {
// btn3.addEventListener("click",function(){document.body.innerHTML += "btn3 clicked! <br />"},true);
//}
</script>
</html>
<div id="test"></div>
<script type="text/javascript">
var btn3 = document.getElementById("btn3");
var id = document.getElementById('test');
btn3.onclick = function(){
id.innerHTML += "click!<br>";
}
</script>