凑合一下：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
<html>
<head>
<title>div自适应</title>
<style type="text/css">
#dMain {
margin:0 auto;
width:90%;
display:table;
#position:relative;
}
#dLeft {
float:left;
height:300px;
background:#C1C1FF;
}
#dCenter {
display:table-cell;
align:center;
#position:absolute;
#left:50%;
width:380px;
height:300px;
}
#dCenter div{
#position:relative;
#left:-50%;
width:380px;
height:300px;
background:#FFC1FF;
}
#dRight {
float:right;
height:300px;
background:#C8E3E3;
}
</style>
</head>
<body>
<b>3个部分，中间宽度固定，左右根据内容自适应，如何实现不管左右的宽度怎样变化，dCenter始终居中？</b>
<div id="dMain">
<div id="dLeft">1111111</div>
<div id="dCenter"><div>2222222222222</div></div>
<div id="dRight">3333333333333</div>
</div>
</body>
</html>
