Opc.Ua.Com.Client.ComDaGroup.SyncWrite C# (CSharp) Method

        public int[] SyncWrite(int[] serverHandles, object[] values, int count)
        {
            // initialize output parameters.
            IntPtr pErrors = IntPtr.Zero;

            string methodName = "IOPCSyncIO.Write";

            try
            {
                IOPCSyncIO server = BeginComCall<IOPCSyncIO>(methodName, true);

                server.Write(
                    count,
                    serverHandles,
                    values,
                    out pErrors);
            }
            catch (Exception e)
            {
                ComUtils.TraceComError(e, methodName);
                return null;
            }
            finally
            {
                EndComCall(methodName);
            }

            // unmarshal output parameters.
            return ComUtils.GetInt32s(ref pErrors, count, true);
        }

        /// <summary>
        /// Writes the item values to servers.
        /// </summary>
        /// <param name="requests">The requests.</param>
        private void Da20WriteItemValues(List<WriteRequest> requests)
        {
            //lock (m_groupLock)
            {
                //if (m_group == null)
                //{
                    ComDaGroup m_group = new ComDaGroup(this, false);
                //}

                try
                {
                    int count1 = 0;
                    GroupItem[] items = new GroupItem[requests.Count];
                    WriteRequest[] addItemRequests = new WriteRequest[requests.Count];
                    object[] convertedValues = new object[requests.Count];

                    // create the items in the temporary group.
                    for (int ii = 0; ii < requests.Count; ii++)
                    {
                        WriteRequest request = requests[ii];

                        if (request == null)
                        {
                            continue;
                        }

                        // status code writes not supported.
                        if (request.Value.StatusCode != StatusCodes.Good)
                        {
                            request.Error = ResultIds.E_NOTSUPPORTED;
                            continue;
                        }

                        // timestamp writes not supported.
                        if (request.Value.ServerTimestamp != DateTime.MinValue)
                        {
                            request.Error = ResultIds.E_NOTSUPPORTED;
                            continue;
                        }

                        // timestamp writes not supported.
                        if (request.Value.SourceTimestamp != DateTime.MinValue)
                        {
                            request.Error = ResultIds.E_NOTSUPPORTED;
                            continue;
                        }

                        // convert to a DA compatible type.
                        object convertedValue = null;
                        request.Error = ComDaClientNodeManager.LocalToRemoteValue(request.Value.WrappedValue, out convertedValue);

                        if (request.Error < 0)
                        {
                            continue;
                        }

                        // add the item.
                        items[count1] = m_group.CreateItem(request.ItemId, 0, 0, true);
                        addItemRequests[count1] = request;
                        convertedValues[count1] = convertedValue;
                        count1++;
                    }

                    // create the items on the server.
                    m_group.ApplyChanges();

                    // build the list of values to write.
                    int count2 = 0;
                    int[] serverHandles = new int[count1];
                    object[] values = new object[count1];
                    WriteRequest[] writeRequests = new WriteRequest[count1];

                    for (int ii = 0; ii < count1; ii++)
                    {
                        // check for error on create.
                        GroupItem item = items[ii];
                        WriteRequest request = addItemRequests[ii];

                        if (item.ErrorId < 0)
                        {
                            request.Error = item.ErrorId;
                            continue;
                        }

                        serverHandles[count2] = item.ServerHandle;
                        values[count2] = convertedValues[ii];
                        writeRequests[count2] = request;
                        count2++;
                    }

                    if (count2 > 0)
                    {
                        // write values to the server.
                        int[] errors = m_group.SyncWrite(serverHandles, values, count2);

                        // read the errors.
                        for (int ii = 0; ii < count2; ii++)
                        {
                            if (errors != null && errors.Length > ii)
                            {
                                writeRequests[ii].Error = errors[ii];
                            }
                            else
                            {
                                writeRequests[ii].Error = ResultIds.E_FAIL;
                            }
                        }

                        // delete the items.
                        for (int ii = 0; ii < count1; ii++)
                        {
                            GroupItem item = items[ii];

                            if (item.ErrorId >= 0)
                            {
                                m_group.RemoveItem(item);
                            }
                        }

                        m_group.ApplyChanges();
                    }
                }
                finally
                {
                    // delete the group and items.
                    m_group.Delete();
                }
            }
        }