<div class="TxtBox">
<iframe frameborder="0" scrolling="no" name="news1"  id="news1" onload="if(document.frames['news1'].document.body.scrollHeight>document.frames['news2'].document.body.scrollHeight) document.all.news1.height=document.frames['news1'].document.body.scrollHeight;if(document.frames['news1'].document.body.scrollHeight<=document.frames['news2'].document.body.scrollHeight) document.all.news1.height=document.frames['news2'].document.body.scrollHeight;" src="http://www.jb51.net" width="100%"></iframe>
</div>

<div class="TxtBox">

<iframe frameborder="0" scrolling="no" name="news2" id="news2" onload="if(document.frames['news1'].document.body.scrollHeight>document.frames['news2'].document.body.scrollHeight) document.all.news2.height=document.frames['news1'].document.body.scrollHeight;if(document.frames['news1'].document.body.scrollHeight<=document.frames['news2'].document.body.scrollHeight) document.all.news2.height=document.frames['news2'].document.body.scrollHeight;" src="http://www.jb51.net/index_1.htm" width="100%"></iframe>

</div>
jb51提醒啊，多浏览期兼容需要注意些地方，不要用document.all用兼容好的，