代码简单，兼容性还可以

<script>

function SetWinHeight(obj)

{

 var win=obj;

 if (document.getElementById)

 {

  if (win && !window.opera)

  {

   if (win.contentDocument && win.contentDocument.body.offsetHeight)

   win.height = win.contentDocument.body.offsetHeight;

   else if(win.Document && win.Document.body.scrollHeight)

   win.height = win.Document.body.scrollHeight;

  }

 }

}

</script>

最后，加入iframe,不能丢掉onload属性，当然了，id也必须也函数中的win匹配

<iframe  height="200" id="win" name="win" οnlοad="Javascript:SetWinHeight(this)" frameborder="0" scrolling="no" src="1.htm"></iframe>