原来的代码：
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>框架布局，用Frameset如何实现固定宽度的居中</title>
<head>
</head>
<frameset rows="130,*,40" frameborder="no" border="0" framespacing="0">
<frame src="top.html" name="topFrame" scrolling="No" noresize="noresize" id="topFrame" />
<frame src="center.html" name="mainFrame" id="mainFrame" />
<frame src="bottom.html" name="bottomFrame" scrolling="No" noresize="noresize" id="bottomFrame" />
</frameset>
<noframes>
<body></body>
</noframes>
</html>
====================================================================
改过的代码
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>框架布局，用Frameset如何实现固定宽度的居中</title>
<head>
</head>
<frameset cols="*,1024,*" frameborder="no" border="0" framespacing="0">
<frame src="about:blank"></frame>
<frameset rows="130,*,40" frameborder="no" border="0" framespacing="0">
<frame src="top.html" name="topFrame" scrolling="No" noresize="noresize" id="topFrame" />
<frame src="center.html" name="mainFrame" id="mainFrame" />
<frame src="bottom.html" name="bottomFrame" scrolling="No" noresize="noresize" id="bottomFrame" />
</frameset>
<frame src="about:blank"></frame>
</frameset>
<noframes>
<body></body>
</noframes>
</html>