css固定定位,即懸浮效果(例如對聯廣告),不用JS,CSS中"position:fixed;"即可。
position:fixed; 以視口為包含塊,因此在浏覽器窗口內固定。
IE 6.0不支持,因此采用相對於Html元素的絕對定位。
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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xHtml1-transitional.dtd">
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<Html XMLns="http://www.w3.org/1999/xHtml">
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<head>
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<meta http-equiv="Content-Type" content="text/Html; charset=gb2312" />
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<title>CSS固定定位</title>
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<style type="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:1px solid #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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<!--[if lte IE 6]>
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<style type="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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<div id="fixedLayer">固定不動</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>
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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>
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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>
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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>
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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>
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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>
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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>
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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>
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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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</body>
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</Html>