{pc:content  action="position" posid="2" order="listorder DESC" num="4"}
<div class="boxB boxBHome">

{loop $data $r}
                     <p class="picbox  {if ($n==4)} manone{/if}">
                       <a href="{$v['url']}" class="imgB" target="_blank"><img src="{thumb($v[thumb],90,0)}" alt="{$v['title']}" width="95" height="130"></a>
                       <span><a href="{$v['url']}" target="_blank">{str_cut($v['title'],40)}</a></span>                     </p>
   {/loop}  
   </div>
  {/pc}

此代码亮点在于 <p class="picbox  {if ($n==4)} manone{/if}"> 意思是第4个自动加 'manone'   变成<p class="picbox  manone">