Opc.Ua.Server.CoreNodeManager.ModifyMonitoredItems C# (CSharp) Method

        public void ModifyMonitoredItems(
            OperationContext                  context,
            TimestampsToReturn                timestampsToReturn,
            IList<IMonitoredItem>             monitoredItems,
            IList<MonitoredItemModifyRequest> itemsToModify,
            IList<ServiceResult>              errors,
            IList<MonitoringFilterResult>     filterErrors)
        { 
            if (context == null)         throw new ArgumentNullException("context");
            if (monitoredItems == null)  throw new ArgumentNullException("monitoredItems");
            if (itemsToModify == null)   throw new ArgumentNullException("itemsToModify");
            if (errors == null)          throw new ArgumentNullException("errors");

            try
            {
                m_lock.Enter();
 
                for (int ii = 0; ii < errors.Count; ii++)
                {
                    MonitoredItemModifyRequest itemToModify = itemsToModify[ii];

                    // skip items that have already been processed.
                    if (itemToModify.Processed || monitoredItems[ii] == null)
                    {
                        continue;
                    }
                    
                    // check if the node manager created the item.                    
                    if (!Object.ReferenceEquals(this, monitoredItems[ii].NodeManager))
                    {
                        continue;
                    }
                                        
                    // owned by this node manager.
                    itemToModify.Processed = true;
                    
                    // validate monitored item.
                    MonitoredItem monitoredItem = null;

                    if (!m_monitoredItems.TryGetValue(monitoredItems[ii].Id, out monitoredItem))
                    {
                        errors[ii] = StatusCodes.BadMonitoredItemIdInvalid;
                        continue;
                    }

                    if (!Object.ReferenceEquals(monitoredItem, monitoredItems[ii]))
                    {
                        errors[ii] = StatusCodes.BadMonitoredItemIdInvalid;
                        continue;
                    }
                    
                    // find the node being monitored.
                    ILocalNode node = monitoredItem.ManagerHandle as ILocalNode;

                    if (node == null)
                    {
                        errors[ii] = StatusCodes.BadNodeIdUnknown;
                        continue;
                    }

                    // fetch the metadata for the node.
                    NodeMetadata metadata = GetNodeMetadata(context, monitoredItem.ManagerHandle, BrowseResultMask.All);
                                        
                    bool rangeRequired = false;

                    // validate the filter against the node/attribute being monitored.
                    errors[ii] = ValidateFilter(
                        metadata,
                        monitoredItem.AttributeId,
                        itemToModify.RequestedParameters.Filter,
                        out rangeRequired);

                    if (ServiceResult.IsBad(errors[ii]))
                    {
                         continue;
                    }
                                      
                    // lookup EU range if required.
                    Range range = null;

                    if (rangeRequired)
                    {
                        // look up EU range.
                        errors[ii] = ReadEURange(context, node, out range);
                                                
                        if (ServiceResult.IsBad(errors[ii]))
                        {
                             continue;
                        }
                    }

                    // update sampling.
                    errors[ii] = m_samplingGroupManager.ModifyMonitoredItem(
                        context,
                        timestampsToReturn,
                        monitoredItem,
                        itemToModify,
                        range);
                    
                    // state of item did not change if an error returned here.
                    if (ServiceResult.IsBad(errors[ii]))
                    {
                        continue;
                    }

                    // item has been modified successfully. 
                    // errors updating the sampling groups will be reported in notifications.
                    errors[ii] = StatusCodes.Good;
                }
            }
            finally
            {
                m_lock.Exit();
            }

            // update all sampling groups.
            m_samplingGroupManager.ApplyChanges();
        }