封装可视区域大小的函数

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<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
<head>
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    <title>Document</title>
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<body>

</body>
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        if(window.innerWidth!=null){
            return {
                window.innerWidth,
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                document.documentElement.clientWidth,
                height:document.documentElement.clientHeight
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            return{
                document.body.clientWidth,
                height:document.body.clientHeight
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    document.write(client().width);
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