CAllIBlockElement::getIndexedProperties

protected function getIndexedProperties(int $iblockId): ?array
{
	if ($iblockId <= 0)
	{
		return null;
	}
	if (!isset($this->indexedProperties[$iblockId]))
	{
		$this->indexedProperties[$iblockId] = $this->getPropertiesByFilter(array(
			'=IBLOCK_ID' => $iblockId,
			'=ACTIVE' => 'Y',
			'=SEARCHABLE' => 'Y'
		));
		if (empty($this->indexedProperties[$iblockId]))
		{
			$this->indexedProperties[$iblockId] = array();
		}
	}
	return (!empty($this->indexedProperties[$iblockId]) ? $this->indexedProperties[$iblockId] : null);
}