public function category($arCategoryIDList, $bWithChildren = false)
    {
        if (!is_array($arCategoryIDList)) {
            $arCategoryIDList = [$arCategoryIDList];
        }

        $arResultIDList = [];
        foreach ($arCategoryIDList as $iCategoryID) {
            $arResultIDList = array_merge($arResultIDList, (array) ProductListStore::instance()->category->get($iCategoryID));
            if ($bWithChildren) {
                $arResultIDList = array_merge($arResultIDList, (array) $this->getIDListChildrenCategory($iCategoryID));
            }
        }

        return $this->intersect($arResultIDList);
    }