任务：一个页面里包含两个iframe（暂且叫left iframe和right iframe），现在要求right iframe加载一个特定页面时，立即将此页面在主窗口显示。
这里设计3个页面，index.html、left.html、right.html。其中index中有两个iframe(left iframe和right iframe), left iframe显示页面为left.html，right iframe显示为right.html。
Index.html:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>index</title>
</head>
<body>
<div id="container">
<iframe src="left.htm" name="leftFrame" width="20%" height="100%" align="middle" scrolling="no" />
<iframe src="right.html" id="platformFrame" name="platformFrame" width="80%" height="100%" align="middle" scrolling="auto"/>
</div>
</body>
</html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>index</title>
</head>
<body>
<div id="container">
<iframe src="left.htm" name="leftFrame" width="20%" height="100%" align="middle" scrolling="no" />
<iframe src="right.html" id="platformFrame" name="platformFrame" width="80%" height="100%" align="middle" scrolling="auto"/>
</div>
</body>
</html>
Left.html:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>index</title>
</head>
<body>
left
</body>
</html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>index</title>
</head>
<body>
left
</body>
</html>
Right.html:
<html>
<head></head>
<body>
right
</body>
<script type="text/javascript" language="javascript">
<!--:最顶层窗口 window.self:当前窗口 -->
if (!=window.self)
{
.location='right.html'
}
</script>
</html>
<head></head>
<body>
right
</body>
<script type="text/javascript" language="javascript">
<!--:最顶层窗口 window.self:当前窗口 -->
if (!=window.self)
{
.location='right.html'
}
</script>
</html>
以上最主要的就是就是这段JavaScript：
if (!=window.self)
{
.location='right.html'
}
它的意思就是当right.html不为顶层窗口时将它设置为顶层窗口。
当right.html没有这段js时点击index.html页面，将如下显示：
当right.html有这段js时点击index.html页面，将如下显示：
