CAllCrmSonetSubscription::IsRelationRegistered

static function IsRelationRegistered($entityTypeID, $entityID, $typeID, $userID)
{
	if(!CCrmOwnerType::IsDefined($entityTypeID))
	{
		return false;
	}

	$userID = intval($userID);
	$entityID = intval($entityID);
	if($userID <= 0 || $entityID <= 0)
	{
		return false;
	}

	$filter = array(
		'SL_ENTITY_TYPE' => CCrmLiveFeedEntity::GetByEntityTypeID($entityTypeID),
		'ENTITY_ID' => $entityID,
		'USER_ID' => $userID
	);

	$typeID = intval($typeID);
	if(CCrmSonetSubscriptionType::IsDefined($typeID))
	{
		$filter['TYPE_ID'] = $typeID;
	}

	$dbResult = CCrmSonetSubscription::GetList(array(), $filter, array(), false, array('TYPE_ID'));
	return is_int($dbResult) ? $dbResult > 0 : false;
}