导航选中状态js写法

<div class="h_sidenav" id="h_sidenav">
    <a href="<?php  echo site_url('user')?>">用户首页</a>
    <a href="<?php  echo site_url('user/trade')?>">交易信息</a>
    <a href="<?php  echo site_url('user/password')?>">密码修改</a>
    <a href="<?php  echo site_url('user/info')?>">我的信息 </a>
    <a href="<?php  echo site_url('user/recharge')?>">充值 提现 转帐</a>
    <a href="<?php  echo site_url('user/others')?>">其余问题</a>
</div>
    <script type="text/javascript">
       window.onload = function(){
            var url = window.location.href;
            var div = document.getElementById('h_sidenav');
            for(var i=0;i<div.childNodes.length;i++){
                if(div.childNodes[i].nodeType == 1 &&  div.childNodes[i] ==url){
                    div.childNodes[i].setAttribute('class','cur');//class = 'cur' 是选中类
                    break;
                }
            }
       }
    </script>

节点类型	NodeType
元素element	1
属性attr	2
文本text	3
注释comments	8
文档document	9