['in', $picId]], null, 'picId,categoryId'); $data = []; if (!empty($list)) { foreach ($list as $key => $val) { $picId = $val['picId']; $categoryId = $val['categoryId']; $data[$picId][] = $categoryId; } $data = is_array($id) ? $data : array_pop($data); } return $data; } }