第一种方法：代码简单，兼容性还可以，大家可以先测试下。
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;
}
}
}
<iframe width="778" align="center" height="200" id="win" name="win" onload="Javascript:SetWinHeight(this)" frameborder="0" scrolling="no" src="1.htm"></iframe> 2.经典代码 iFrame 自适应高度，在IE6/IE7/IE8/Firefox/Opera/Chrome/Safari通过测试。
HTML代码:
<iframe src="http://www.fufuok.com/" id="iframepage" name="iframepage" frameBorder=0 scrolling=no width="100%" onLoad="iFrameHeight()" ></iframe>Javascript代码：
<script type="text/javascript" language="javascript">
function iFrameHeight() {
var ifm= document.getElementById("iframepage");
var subWeb = document.frames ? document.frames["iframepage"].document : ifm.contentDocument;
if(ifm != null && subWeb != null) {
ifm.height = subWeb.body.scrollHeight;
}
}
</script>
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