如何点击IE窗口上方的“Ｘ关闭符号”，弹出提示窗口呢？
<HTML>
<HEAD>
<TITLE> New Document </TITLE>
<script language="javascript">
function test()
{
return "";
}
</script>
</HEAD>
<BODY onbeforeunload="return test();">
</BODY>
</HTML>
<HEAD>
<TITLE> New Document </TITLE>
<script language="javascript">
function test()
{
return "";
}
</script>
</HEAD>
<BODY onbeforeunload="return test();">
</BODY>
</HTML>
