直接上代码
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<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport"
content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
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<body>
<iframe id="main" name="main" src="http://www.hao123.com/" frameborder="0" width="100%" ></iframe>
</body>
<script>
var ifm= document.getElementById("main");
ifm.height=document.documentElement.clientHeight - 28;
</script>
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