日期:2014-05-17 浏览次数:20790 次
<!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>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
<style type="text/css">
#demo {
border:1px solid #999;
background-color:#EEE;
height:200px;
position:absolute;
top:50%;
margin-top:-100px; /*margin-top值为高度值的50%*/
}
</style>
</head>
<body>
<div id="demo">DEMO</div>
</body>
</html>
------解决方案--------------------
<!DOCTYPE HTML>
<html>
<head>
<meta charset="gb2312" />
<title></title>
<style>
.test {
position:absolute;
width:100px; height:100px;
border:1px solid red;
}
</style>
</head>
<body>
<div class="test" id="test"></div>
<script>
var obj = document.getElementById('test');
obj.style.left = (document.documentElement.clientWidth - obj.clientWidth) / 2 + 'px';
obj.style.top = (document.documentElement.clientHeight - obj.clientHeight) / 2 + 'px';
</script>
</body>
</html>
------解决方案--------------------
http://www.html-5.cn/div-css/jishu/1908.html