index.htm
<HTML>
<FRAMESET rows="33%,*,33%">
<FRAME name="t_frame" src="1.html">
<FRAME name="m_frame" src="2.html">
<FRAME name="b_frame" src="3.html">
</FRAMESET>
</HTML>
1.html
<HEAD>
<SCRIPT language="JavaScript">
<!--
function twoframes() {
parent.m_frame.location="4.html";
parent.b_frame.location="5.html";
}
//-->
</SCRIPT>
</HEAD>
<BODY>
This is frame 1, the top frame: <A HREF="javascript:twoframes();">Change the two lower frames</A>
</BODY>
2.html
<HEAD>
</HEAD>
<BODY>
This is frame 2, the middle frame.
</BODY>
3.html
<HEAD>
</HEAD>
<BODY>
This is frame 3, the bottom frame.
</BODY>
4.html
<HEAD>
</HEAD>
<BODY>
This is frame 4, the new middle frame.
</BODY>
5.html
<HEAD>
</HEAD>
<BODY>
This is frame 5, the new bottom frame.
</BODY>