1、一层嵌套:
{foreach from=$categories item=cat}
{$cat.name}
{/foreach}
2、二层嵌套:
{foreach from=$categories item=cate}
{foreach from=$cat.cat_id item=child}
{$child.name}
{/foreach}
{/foreach}
3、三层嵌套:
{foreach from=$categories item=cate}
{foreach from=$cat.cat_id item=child}
{foreach from=$child.cat_id item=childer}
{$childer.name}
{/foreach}
{/foreach}
{/foreach}