EventManager::addEventHandler

public function addEventHandler($entity, $eventType, $callback, $includeFile = false, $sort = 100)
{
	$entity = static::obtainEntity($entity);
	$eventType = static::obtainEventType($entity, $eventType);

	// subscribe
	return \Bitrix\Main\EventManager::getInstance()
		->addEventHandler($entity->getModule(), $eventType, $callback, $includeFile, $sort);
}