ImageRepository::getCollectionByParent

public function getCollectionByParent(BaseIblockElementEntity $element): ImageCollection
{
	$collection = $this->factory->createCollection();
	if ($element->isNew())
	{
		return $collection;
	}

	$items = [];

	$previewValue = (int)$element->getField(PreviewImage::CODE);
	if ($previewValue > 0)
	{
		$previewEntity = $this->getEntityById($previewValue, ImageFactory::PREVIEW_IMAGE);
		if ($previewEntity)
		{
			$items[] = $previewEntity;
		}
	}

	$detailValue = (int)$element->getField(DetailImage::CODE);
	if ($detailValue > 0)
	{
		$detailEntity = $this->getEntityById($detailValue, ImageFactory::DETAIL_IMAGE);
		if ($detailEntity)
		{
			$items[] = $detailEntity;
		}
	}

	foreach ($this->getMorePhotoEntities($element) as $item)
	{
		$items[] = $item;
	}

	if (!empty($items))
	{
		$collection->add(...$items);
	}

	return $collection;
}