易优cms当前栏目怎么调用顶级栏目字段

{eyou:channel type='first' currentstyle='on'}
<a href="{$field.typeurl}" class="{$field.currentstyle}">{$field.typename}</a>
{/eyou:channel}

{eyou:channel type='sonself' currentstyle='on'}
<a href="{$field.typeurl}" class="{$field.currentstyle}">{$field.typename}</a>
{/eyou:channel}