Opc.Ua.Client.Session.AsyncRequestCompleted C# (CSharp) Method

        private void AsyncRequestCompleted(IAsyncResult result, uint requestId, uint typeId)
        {
            lock (m_outstandingRequests)
            {
                // remove the request.
                AsyncRequestState state = RemoveRequest(result, requestId, typeId);
                
                if (state != null)
                {
                    // mark any old requests as default (i.e. the should have returned before this request).
                    DateTime maxAge = state.Timestamp.AddSeconds(-1);

                    for (LinkedListNode<AsyncRequestState> ii = m_outstandingRequests.First; ii != null; ii = ii.Next)
                    {
                        if (ii.Value.RequestTypeId == typeId && ii.Value.Timestamp < maxAge)
                        {
                            ii.Value.Defunct = true;
                        }
                    }
                }

                // add a dummy placeholder since the begin request has not completed yet.
                if (state == null)
                {
                    state = new AsyncRequestState();

                    state.Defunct = true;
                    state.RequestId  = requestId;
                    state.RequestTypeId = typeId;
                    state.Result = result;
                    state.Timestamp = DateTime.UtcNow;

                    m_outstandingRequests.AddLast(state);
                }
            }
        }