JS实现标签页选中

                <ul>
                    <li><a id="first_nav" href="list.aspx">全部</a> </li>
                    <li><a id="myTopic" href="list.aspx?act=my" class="">我的发言</a> </li>
                </ul>

   

<script language="JavaScript" type="text/javascript">
        var cid =window.location.search.replace("?act=","");
        if(cid){
            getObj('myTopic').className='current_tab';
        }else{
         getObj('first_nav').className='current_tab';
        }
        function getObj(id) {
         return document.getElementById(id);
        }
    </script>