<html>
<head>
<script type="text/javascript">
window.onload = function(){
var bd = document.getElementsByTagName('body')[0];
bd.onkeypress = function(ev){
ev = ev || window.event;//ie不支持function参数ev
alert(ev.keyCode || ev.which);//火狐不支持keyCode
}
}
</script>
<style type="text/css">
#par{width:300px;height:200px;background:gray;}
#son{width:200px;height:100px;background:green;}
</style>
</head>
<body>
<div id="par">
<div id="son"></div>
</div>
</body>
</html>