.clear{clear:both; height:0px; overflow:hidden;}         .tab{width:400px; font-size:12px;}         .tab_menu ul{padding:0px;margin:0px;}         .tab_menu li{list-style:none; display:block; float:left;             background:#C2CEFE; height:22px; line-height:22px;             padding: 0px 8px; margin-right:6px; border:#86B4CA 1px solid;         }         .box{width:400px; height:200px; overflow:hidden; border:#A8C9D9 1px solid; padding:10px 8px; }         .tab_menu ul li.selected{background:#dadada; cursor:pointer; }         .hide{display:none;}

        $(function() {             var $menu_li = $("div.tab_menu ul li");  //选取网页选项卡             $menu_li.click(function(){                 $(this).addClass("selected") //当前<li>高亮                         .siblings().removeClass("selected"); //去掉其它同辈<li>的高亮                 var index = $menu_li.index( $(this) ); //找到<li>子节点的索引                 $("div.tab_box > div").eq(index).show() //索引为N的DIV显示出来                         .siblings().hide();            //其它的选项卡隐藏             })         }) 

 <div class="tab">     <div class="tab_menu">         <ul>             <li class="selected">个人信息</li>             <li class="selected">我的照片</li>             <li class="selected">我的博客</li>             <div class="clear"></div>         </ul>     </div>     <div class="tab_box">         <div class="box">我的QQ:123456</div>         <div class="box hide">hi </div>         <div class="box hide"> hello <br> </div>     </div> </div>