Opc.Ua.EventFilter.AddSelectClause C# (CSharp) Method

        public void AddSelectClause(NodeId eventTypeId, QualifiedName propertyName)
        {
            SimpleAttributeOperand clause = new SimpleAttributeOperand();

            clause.TypeDefinitionId = eventTypeId;
            clause.AttributeId      = Attributes.Value;

            clause.BrowsePath.Add(propertyName);

            SelectClauses.Add(clause);
        }

        public Result <DataResponse> GetEventData(OpcUAQuery query, NodeId startNodeId, Opc.Ua.EventFilter eventFilter)
        {
            var nodeCache = _nodeCacheFactory.Create(_session);

            eventFilter.AddSelectClause(ObjectTypeIds.BaseEventType, "SourceNode");
            eventFilter.AddSelectClause(ObjectTypeIds.BaseEventType, "EventType");

            var eventFilterValues = GetEventFilterValues(startNodeId, eventFilter);

            if (eventFilterValues == null)
            {
                var monitorItem = AddMonitorItem(startNodeId, eventFilter);
                eventFilterValues = new EventFilterValues(monitorItem, query, eventFilter);
                if (!TryAddEventFilterValues(startNodeId, eventFilterValues))
                {
                    RemoveMonitorItem(monitorItem);
                    eventFilterValues = null;
                }
            }

            lock (_eventData)
            {
                if (eventFilterValues == null)
                {
                    eventFilterValues = GetEventFilterValues(startNodeId, eventFilter);
                }
                if (eventFilterValues != null)
                {
                    return(_eventDataResponse.CreateEventSubscriptionDataResponse(eventFilterValues.Values.Values, query, nodeCache));
                }
            }
            return(new Result <DataResponse>(StatusCodes.BadUnexpectedError, ""));
        }