discuz 帖子列表页调用封面图片代码

$threada= C::t('forum_attachment')->fetch_all_by_id('tid', $thread['tid'], 'aid');$threadaid = reset($threada);$threadpic = C::t('forum_attachment_n')->fetch_by_aid_uid($threadaid['tableid'], $threadaid['aid'], $thread['authorid']);$thread['pic'] = $threadpic['attachment'];