简单的弹出窗口实例

例子
1.htm
===========
<title>1</title>
<input type=button value="open 2" onclick="window.showModalDialog('2.htm',window);">
<script>
alert("1")
</script>

2.htm
===========
<title>2</title>
<frameset cols="0,*">
<frame src="">
<frame src="b.htm">
</frameset>

b.htm
==========
<input type=button value="open 3" onclick="window.showModalDialog('3.htm',window);">
<script>
alert("我是2")
</script>

3.htm
=========
<title>3</title>
<frameset cols="0,*">
<frame src="">
<frame src="c.htm" name="x">
</frameset>

c.htm
=====
<input type="button" value="refresh 2 and close me" onclick="window.dialogArguments.location='2.htm';window.parent.close()">