IE事件处理程序没效果，提示“Object doesn't support property or method 'attachEvent'”
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<style>
.ee{text-decoration:line-through; text-decoration:underline; }
</style>
</head>
<body>
<input type="button" id="btn3" value="按下去3">
<script type="text/javascript">
function ee(){
alert("Hello Haa!");
}
var btn3 = document.getElementById("btn3");
btn3.attachEvent('onclick',ee);
</script>
</body>
</html>
