PbootCMS内页子栏目当前栏目如何实现高亮显示

{pboot:nav num=10 parent={sort:tcode}}
{pboot:if('[nav:scode]'=='{sort:scode}')}
<li><a class="biglink left_active" href="[nav:link]">[nav:name]</a></li>
{else}
<li><a class="biglink" href="[nav:link]">[nav:name]</a></li>
{/pboot:if}
{/pboot:nav}