解决document.body.clientHeight没给你你想要的现象
demo.html
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html xmlns=" http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>Eletric Power Integrative System</title>
<style type="text/css">
html, body {
width: 100%;
height: 100%;
margin: 0px;
padding: 0px;
}
</style>
<script type="text/javascript">
function $(id) {
return document.getElementById(id);
}
window.onload = window.onresize = function() {
$('cententMain').style.height = (document.body.clientHeight - 100) + 'px';
//alert($('cententMain').style.height);
}
</script>
</head>
<body>
<table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td>
<div id="header" style="height:75px; background:#006F68; left:0px; top:0px; width:100%; z-index:1000"></div>
</td>
</tr>
<tr>
<td>
<div id="cententMain" style="background-color:#fff;
position:absolute; left:0px; top:75px; bottom:25px; width:100%;
z-index:100">
<iframe id="indexFrame" name="indexFrame" src="http://www.xjgc.com" width="100%" height="100%" frameborder="1"></iframe>
</div>
</td>
</tr>
<tr>
<td>
<div id="footer" style="background:#006F68; border-top:1px solid
#1291a9; height:25px; position:absolute; left:0px; bottom:0px;
width:100%; z-index:1000" align="center" valign="bottom">
<span style="font-size:11px;color:#fff;font-family:Verdana,
Arial, Helvetica, sans-serif;">©2008 - 2012
Icesoft</span>
</div>
</td>
</tr>
</table>
</body>
</html>
