在使用IFrame的时候经常出现内容高度不符影响页面整体效果，利用JavaScript可以实现Iframe自适应其加载的内容高度．
//main.htm:<html> <head> <meta http-equiv='Content-Type' content='text/html; charset=gb2312' /> <meta name='author' content='F.R.Huang(meizz梅花雪)//www.meizz.com' /> <title>iframe自适应加载的页面高度</title> </head> <body><iframe src="child.htm"></iframe></body></html>//child.htm:<html> <head> <meta http-equiv='Content-Type' content='text/html; charset=gb2312' /> <meta name='author' content='F.R.Huang(meizz梅花雪)//www.meizz.com' /> <title>iframe 自适应其加载的网页(多浏览器兼容)</title> 
<script type="text/javascript">
<!--function iframeAutoFit()
{
var ex;try{if(window!=parent){var a = parent.document.getElementsByTagName("IFRAME");for(var i=0; i<a.length; i++) //author:meizz{if(a[i].contentWindow==window){var h1=0, h2=0;if(document.documentElement&&document.documentElement.scrollHeight){h1=document.documentElement.scrollHeight;
}if(document.body) h2=document.body.scrollHeight;var h=Math.max(h1, h2);if(document.all) {h += 4;}if(window.opera) {h += 1;}a[i].style.height = h +"px";}}}}catch (ex){}}if(document.attachEvent){window.attachEvent("onload", iframeAutoFit);window.attachEvent("onresize", iframeAutoFit);}else{window.addEventListener('load', iframeAutoFit, false);window.addEventListener('resize', iframeAutoFit, false);}
//--></script> </head> <body><table border="1" width="200" style="height: 400px; background-color: yellow"><tr><td>iframe 自适应其加载的网页(多浏览器兼容，支持XHTML)</td></tr></table></body> </html>