<html>
<head>
<script type="text/javascript">
function getEventType(event)
{
alert(event.type);
}
</script>
</head>
<body onmousedown="getEventType(event)">
<p>在文档中点击某个位置。消息框会提示出被触发的事件的类型。</p>
</body>
</html>