css固定定位,即悬浮效果(例如对联广告),不用js,css中"position:fixed;"即可。
position:fixed; 以视口为包含块,因此在浏览器窗口内固定。
ie 6.0不支持,因此采用相对于html元素的绝对定位。
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<!DOCTYPEhtmlPUBLIC"-//W3C//DTDXHTML1.0Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<htmlxmlns="http://www.w3.org/1999/xhtml">
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<head>
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<metahttp-equiv="Content-Type"content="text/html;charset=gb2312"/>
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<title>CSS固定定位</title>
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<styletype="text/css">...
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*{...}{
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padding:0;
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margin:0;
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}
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#fixedLayer{...}{
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width:100px;
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line-height:50px;
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background:#FC6;
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border:1pxsolid#F90;
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position:fixed;
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left:10px;
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top:10px;
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}
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</style>
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<!--[iflteIE6]>
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<styletype="text/css">
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html{
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height:100%;
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overflow:hidden;
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}
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body{
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height:100%;
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overflow:auto;
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}
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#fixedLayer{
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position:absolute;
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}
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</style>
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<![endif]-->
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</head>
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<body>
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<divid="fixedLayer">固定不动</div>
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<p>dd</p>
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<p>dd</p>
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<p>dd</p>
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<p>dd</p>
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<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>
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<p>dd</p>
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<p>dd</p>
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<p>dd</p>
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<p>dd</p>

<p>dd</p>
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<p>dd</p>
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<p>dd</p>
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<p>dd</p>
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<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>
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<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>

<p>dd</p>
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<p>dd</p>
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