TypeFile::getExtensionByMimeType

static function getExtensionByMimeType($mimeType)
{
	$mimes = static::getMimeTypeExtensionList();
	$mimes = array_flip($mimes);
	$mimeType = mb_strtolower($mimeType);
	if (isset($mimes[$mimeType]))
	{
		return $mimes[$mimeType];
	}

	return null;
}