织梦文章页如何获取当前栏目下二级栏目和三级栏目

{dede:channelartlist }
 <dd>
    <dl>
      <dt><a href="{dede:field name='typeurl'/}">{dede:field name='typename'/}</a></dt>
      <dd>
        <ul>
         {dede:sql sql='Select * from `dede_arctype` where reid=~id~ ORDER BY id'}
        <li><a href="[field:typedir function="cn_substr(@me,200,9) " /]">[field:typename/]</a></li>
        {/dede:sql}
        </ul>
      </dd>
    </dl>
  </dd>
 {/dede:channelartlist}