sdk/samples/all in on code/Visual Studio 2010/CSASPNETReverseAJAX/Client.cs

   1 /****************************** Module Header ******************************\
   2 * Module Name:    Client.cs
   3 * Project:        CSASPNETReverseAJAX
   4 * Copyright (c) Microsoft Corporation
   5 *
   6 * Client class is used to synchronize the message sending and the message receiving.
   7 * When DequeueMessage method is called, the method will wait until a new message
   8 * is inserted by calling EnqueueMessage method. This class benefits ManualResetEvent
   9 * class to achieve the synchronism.
  10 *
  11 * This source is subject to the Microsoft Public License.
  12 * See http://www.microsoft.com/opensource/licenses.mspx#Ms-PL.
  13 * All other rights reserved.
  14 *
  15 \*****************************************************************************/
  16
  17 using System.Collections.Generic;
  18 using System.Threading;
  19
  20 namespace CSASPNETReverseAJAX
  21 {
  22     /// <summary>
  23     /// This class represents a web client which can receive messages.
  24     /// </summary>
  25     public class Client
  26     {
  27         private ManualResetEvent messageEvent = new ManualResetEvent(false);
  28         private Queue<Message> messageQueue = new Queue<Message>();
  29
  30         /// <summary>
  31         /// This method is called by a sender to send a message to this client.
  32         /// </summary>
  33         /// <param name="message">the new message</param>
  34         public void EnqueueMessage(Message message)
  35         {
  36             lock (messageQueue)
  37             {
  38                 messageQueue.Enqueue(message);
  39
  40                 // Set a new message event.
  41                 messageEvent.Set();
  42             }
  43         }
  44
  45         /// <summary>
  46         /// This method is called by the client to receive messages from the message queue.
  47         /// If no message, it will wait until a new message is inserted.
  48         /// </summary>
  49         /// <returns>the unread message</returns>
  50         public Message DequeueMessage()
  51         {
  52             // Wait until a new message.
  53             messageEvent.WaitOne();
  54
  55             lock (messageQueue)
  56             {
  57                 if (messageQueue.Count == 1)
  58                 {
  59                     messageEvent.Reset();
  60                 }
  61                 return messageQueue.Dequeue();
  62             }
  63         }
  64     }
  65 }