Opc.Ua.Com.Client.ComAeClientNodeManager.SubscribeToEvents C# (CSharp) Method

        protected override ServiceResult SubscribeToEvents(
            ServerSystemContext context,
            NodeState source,
            IEventMonitoredItem monitoredItem,
            bool unsubscribe)
        {
            ComAeClientManager system = (ComAeClientManager)this.SystemContext.SystemHandle;
            ComAeClient client = (ComAeClient)system.SelectClient(context, false);

            // need to wait until the cache is refreshed for the first time.
            if (!WaitForTypeCache())
            {
                return StatusCodes.BadOutOfService;
            }

            lock (Lock)
            {
                SubscriptionIndex index = new SubscriptionIndex();
                index.NodeId = source.NodeId;
                index.LocaleId = client.LocaleId;

                if (unsubscribe)
                {
                    ComAeSubscriptionClient subscription = null;

                    if (!m_monitoredItems.TryGetValue(monitoredItem.Id, out subscription))
                    {
                        return ServiceResult.Good;
                    }

                    m_monitoredItems.Remove(monitoredItem.Id);
                    // Utils.Trace("REMOVED ITEM {0}", monitoredItem.Id);

                    if (subscription.RemoveItem(monitoredItem as MonitoredItem) == 0)
                    {
                        subscription.Delete();
                        m_subscriptions.Remove(index);
                        // Utils.Trace("DELETED SUBSCRIPTION {0}", index.NodeId);
                    }
                }
                else
                {
                    ComAeSubscriptionClient subscription = null;

                    if (!m_subscriptions.TryGetValue(index, out subscription))
                    {
                        subscription = new ComAeSubscriptionClient(context, m_configuration, m_typeCache, NamespaceIndex, system, monitoredItem as MonitoredItem);
                        m_subscriptions.Add(index, subscription);
                        subscription.Create();
                        // Utils.Trace("ADDED NEW SUBSCRIPTION {0}", index.NodeId);
                    }
                    else
                    {
                        subscription.AddItem(monitoredItem as MonitoredItem);
                    }

                    m_monitoredItems[monitoredItem.Id] = subscription;
                    // Utils.Trace("ADDED NEW ITEM {0}", monitoredItem.Id);
                }
            }

            // all done.
            return ServiceResult.Good;
        }