Opc.Ua.Bindings.TcpClientChannel.BeginSendRequest C# (CSharp) Method

        public IAsyncResult BeginSendRequest(IServiceRequest request, int timeout, AsyncCallback callback, object state)
        {
            if (request == null) throw new ArgumentNullException("request");
            if (timeout <= 0) throw new ArgumentException("Timeout must be greater than zero.", "timeout");

            lock (DataLock)
            {
                bool firstCall = false;
                WriteOperation operation = null;

                // check if this is the first call.
                if (State == TcpChannelState.Closed)
                {
                    if (m_queuedOperations == null)
                    {
                        firstCall = true;
                        m_queuedOperations = new List<QueuedOperation>();
                    }
                }

                // queue operations until connect completes.
                if (m_queuedOperations != null)
                {
                    operation = BeginOperation(timeout, callback, state);
                    m_queuedOperations.Add(new QueuedOperation(operation, timeout, request));

                    if (firstCall)
                    {
                        BeginConnect(m_url, timeout, OnConnectOnDemandComplete, null);
                    }

                    return operation;
                }

                if (State != TcpChannelState.Open)
                {
                    throw new ServiceResultException(StatusCodes.BadConnectionClosed);
                }

                //Utils.Trace("Channel {0}: BeginSendRequest()", ChannelId);

                if (m_reconnecting)
                {
                    throw ServiceResultException.Create(StatusCodes.BadRequestInterrupted, "Attempting to reconnect to the server.");
                }

                // send request.
                operation = BeginOperation(timeout, callback, state);
                SendRequest(operation, timeout, request);
                return operation;
            }
        }