动态为事件添加js代码示例

复制代码代码如下:
<HTML>
<HEAD>
<script language="javascript">
attachEvent（"onblur", blur）;
function blur（）
{
document.all.form.username.attachEvent（"onblur", blur）;
if（event.srcElement == document.all.form.username）{
alert（"efewef"）;
}
}
</script>
</HEAD>
<BODY>
<form name="form">
<input type="text" name="username" onblur="alert（"hello"）">
</form>
</BODY>

其执行顺序为:
先执行alert（"hello"）;
后执行alert（"efewef"）;