并列div自动等高

方法一：css控制

 <!DOCTYPE html>

 <html lang="en">

 <head>

     <meta charset="UTF-8">

     <meta http-equiv="Content-Type" content="text/html; charset=gb2312" />

 <title>完美的DIV三行三列自适应高度布局</title>

 <style type="text/css">

 body {

     margin:0;

     padding:0;

     font-size:12px;

 }

 .header {

     width:100%;

     height:50px;

     background:#EEE;

     border-bottom:1px solid #000;

 }

 .colmask {

     position:relative;

     clear:both;

     width:100%;

     overflow:hidden;

 }

 .colright, .colmid, .colleft {

     float:left;

     width:100%;

     position:relative;

 }

 .col1, .col2, .col3 {

     float:left;

     position:relative;

     overflow:hidden;

 }

 .threecol {

     background:#BBB;

 }

 .threecol .colmid {

     right:20%;

     background:#CCC;

 }

 .threecol .colleft {

     right:60%;

     background:#DDD;

 }

 .threecol .col1 {

     width:58%;

     left:101%;

 }

 .threecol .col2 {

     width:18%;

     left:23%;

 }

 .threecol .col3 {

     width:18%;

     left:85%;

 }

 .footer {

     clear:both;

     width:100%;

     height:50px;

     background:#EEE;

     border-top:1px solid #000;

 }

 </style>

 </head>

 <body>

 <div class="header"> 这里是头部 </div>

 <div class="colmask threecol">

   <div class="colmid">

     <div class="colleft">

       <div class="col1">

         <p>这里是中间</p>

         <p>这里是中间</p>

         <p>这里是中间</p>

         <p>这里是中间</p>

         <p>这里是中间</p>

         <p>这里是中间</p>

         <p>这里是中间</p>

       </div>

       <div class="col2"> 这里是左栏 </div>

       <div class="col3">

         <p>这里是右栏</p>

         <p>这里是右栏</p>

         <p>这里是右栏</p>

         <p>这里是右栏</p>

       </div>

     </div>

   </div>

 </div>

 <div class="footer"> 这里是底部 </div>

 </body>

 </html>

方法二：JS控制

function SetSameHeight(obj1,obj2)

{

     var h1 = $(obj1).outerHeight(); //获取对象1的高度

     var h2 = $(obj2).outerHeight();  //获取对象2高度

     var mh = Math.max( h1, h2); //比较一下

     $(obj1).height(mh);

     $(obj2).height(mh);

}

在页面用调用：

jQuery(document).ready(function($) {

    SetSameHeight(".left",".line");

    SetSameHeight(".right_main",".line");//如果有３个div 就加这一行代码，再适应一次．

}

　　参考博客：http://www.jianshu.com/p/93e61ec8f354