两个常用的DIV弹出层效果代码(遮挡整个页面,遮挡可视部分)

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>DIV弹出层</title>
<meta charset="gbk" />
<style>
 div{
 position:absolute;
 top:0;
 left:0;
 background:#ccc;
 }
</style>
</head>
<body>
<div id="test"></div>
<input onclick="test1()" type="button" value="盖住整个页面"/>
<input onclick="test1(1)" type="button" value="盖住可视的部分"/>
 
 
 
 
</body>
</html>
<script>
 function test1(f){
 var d = document.getElementById('test'),wh = getWH(f);
 d.style.cssText +=";"+wh.w+'px;height:'+wh.h+'px'
 }
 var getWH = function (){
 var d = document,doc = d[d.compatMode == "CSS1Compat"?'documentElement':'body'];
 return function(f){
 return {
 w:doc[(f?'client':'scroll')+'Width'],
 h:f?doc.clientHeight:Math.max(doc.clientHeight,doc.scrollHeight)
 }
 }
 }()
</script>