DeleteFiles::process

public function process(Item $item): Result
{
	$result = new Result();

	$itemBeforeSave = $this->getItemBeforeSave();
	if (!$itemBeforeSave)
	{
		$result->addError(new Error('itemBeforeSave is required in ' . static::class));

		return $result;
	}

	$fileUploader = Container::getInstance()->getFileUploader();
	foreach ($this->fileFields as $field)
	{
		$fileIds = (array)$itemBeforeSave->get($field->getName());
		foreach ($fileIds as $fileId)
		{
			$fileUploader->deleteFilePersistently((int)$fileId);
		}
	}

	return $result;
}