phpcmsv9导航默认进入第一个子栏目

<div class="nav">
<div class="wrapper">
<ul class="yj">

{pc:content action="category" catid="0" num="8" siteid="$siteid" order="listorder ASC"}
<li><a href="{siteurl($siteid)}" {if empty($catid)} class="cen" {/if}>首页</a></li>
{loop $data $r}<!--一-->
{if $r[child]==0}<!--1-1-->

<li><a href="{$r[url]}" {if $catid==$r[catid]}  class="cen" {/if} {if $r[type]==2} target="_blank"{/if}>{$r[catname]}</a></li>
{else}
{php $j=0;}
{php $d=0;}
{php $k=0;}
{loop subcat($r[catid]) $m}		<!--2级的开始-->
{php $j++;}
{if $j==1}
{if $m[child]==0}
{php $xj_url=$m[url];}<!--2级是无子栏目--><!--2-1 url-->
{else}
{loop subcat($m[catid]) $c}<!--3级开始-->
{php $d++;}
{if $d==1}<!--3级下第一个子栏目-->
{if $c[child]==0}
{php $xj_url=$c[url];}<!--3-1 url-->
{else}
{loop subcat($c[catid]) $s}<!--4级的开始-->
{php $k++}
{if $k==1}
{php $xj_url=$s[url];}	<!--4-1-->
{/if}
{/loop}

{/if}
{/if}
{/loop}
{/if}
{/if}
{/loop}

<li><a href="{$xj_url}" {if $catid==$r[catid] || $CATEGORYS[$catid][parentid]==$r[catid] || $x_catid==$r[catid]} class="cen" {/if}>{$r[catname]}</a></li>
{/if}
{/loop}<!--一层 loop结束-->
{/pc}

</ul>
</div>

</div>

<div class="cl"></div>
</div>