C#异步UDP通信

 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Net;
 using System.Net.Sockets;
 using System.Threading;
 namespace AsyncServer
 {
     public class UdpState
     {
         public UdpClient udpClient;
         public IPEndPoint ipEndPoint;
         public const int BufferSize = 1024;
         public byte[] buffer = new byte[BufferSize];
         public int counter = 0;
     }
     public class AsyncUdpSever
     {
         private IPEndPoint ipEndPoint = null;
         private IPEndPoint remoteEP = null;
         private UdpClient udpReceive = null;
         private UdpClient udpSend = null;
         private const int listenPort = 1100;
         private const int remotePort = 1101;
         UdpState udpReceiveState = null;
         UdpState udpSendState = null;
         private ManualResetEvent sendDone = new ManualResetEvent(false);
         private ManualResetEvent receiveDone = new ManualResetEvent(false);
         public AsyncUdpSever()
         {
             ipEndPoint = new IPEndPoint(IPAddress.Any, listenPort);
             remoteEP = new IPEndPoint(Dns.GetHostAddresses(Dns.GetHostName())[0], remotePort);
             udpReceive = new UdpClient(ipEndPoint);
             udpSend = new UdpClient();
             udpReceiveState = new UdpState();
             udpReceiveState.udpClient = udpReceive;
             udpReceiveState.ipEndPoint = ipEndPoint;

             udpSendState = new UdpState();
             udpSendState.udpClient = udpSend;
             udpSendState.ipEndPoint = remoteEP;
         }
         public void ReceiveMsg()
         {
             Console.WriteLine("listening for messages");
             while(true)
             {
                 lock (this)
                 {
                     IAsyncResult iar = udpReceive.BeginReceive(new AsyncCallback(ReceiveCallback), udpReceiveState);
                     receiveDone.WaitOne();
                     Thread.Sleep(100);
                 }
             }
         }
         private void ReceiveCallback(IAsyncResult iar)
         {
             UdpState udpReceiveState = iar.AsyncState as UdpState;
             if (iar.IsCompleted)
             {
                 Byte[] receiveBytes = udpReceiveState.udpClient.EndReceive(iar, ref udpReceiveState.ipEndPoint);
                 string receiveString = Encoding.ASCII.GetString(receiveBytes);
                 Console.WriteLine("Received: {0}", receiveString);
                 //Thread.Sleep(100);
                 receiveDone.Set();
                 SendMsg();
             }
         }

         private void SendMsg()
         {
             udpSend.Connect(udpSendState.ipEndPoint);
             udpSendState.udpClient = udpSend;
             udpSendState.counter ++;

             string message = string.Format("第{0}个UDP请求处理完成！",udpSendState.counter);
             Byte[] sendBytes = Encoding.Unicode.GetBytes(message);
             udpSend.BeginSend(sendBytes, sendBytes.Length, new AsyncCallback(SendCallback), udpSendState);
             sendDone.WaitOne();
         }
         private void SendCallback(IAsyncResult iar)
         {
             UdpState udpState = iar.AsyncState as UdpState;
             Console.WriteLine("第{0}个请求处理完毕！", udpState.counter);
             Console.WriteLine("number of bytes sent: {0}", udpState.udpClient.EndSend(iar));
             sendDone.Set();
         }

         public static void Main()
         {
             AsyncUdpSever aus = new AsyncUdpSever();
             Thread t = new Thread(new ThreadStart(aus.ReceiveMsg));
             t.Start();
             Console.Read();
         }
     }
 }

 using System;
 using System.Collections.Generic;
 using System.Text;
 using System.Net;
 using System.Net.Sockets;
 using System.Threading;
 namespace AsyncClient
 {
     public class UdpState
     {
         public UdpClient udpClient = null;
         public IPEndPoint ipEndPoint = null;
         public const int BufferSize = 1024;
         public byte[] buffer = new byte[BufferSize];
         public int counter = 0;
     }
     public class AsyncUdpClient
     {
         public static bool messageSent = false;
         // Receive a message and write it to the console.
         private const int listenPort = 1101;
         private const int remotePort = 1100;
         private IPEndPoint localEP = null;
         private IPEndPoint remoteEP = null;
         private UdpClient udpReceive = null;
         private UdpClient udpSend = null;
         private UdpState udpSendState = null;
         private UdpState udpReceiveState = null;
         private int counter = 0;
         private ManualResetEvent sendDone = new ManualResetEvent(false);
         private ManualResetEvent receiveDone = new ManualResetEvent(false);
         private Socket receiveSocket;
         private Socket sendSocket;
         public AsyncUdpClient()
         {
             localEP = new IPEndPoint(IPAddress.Any, listenPort);
             remoteEP = new IPEndPoint(Dns.GetHostAddresses(Dns.GetHostName())[0],remotePort);
             udpReceive = new UdpClient(localEP);
             udpSend = new UdpClient();

             udpSendState = new UdpState();
             udpSendState.ipEndPoint = remoteEP;
             udpSendState.udpClient = udpSend;

             udpReceiveState = new UdpState();
             udpReceiveState.ipEndPoint = remoteEP;
             udpReceiveState.udpClient = udpReceive;

             receiveSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
             receiveSocket.Bind(localEP);

             sendSocket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
             sendSocket.Bind(remoteEP);
         }
         public void SendMsg()
         {
             udpSend.Connect(remoteEP);

             //Thread t = new Thread(new ThreadStart(ReceiveMessages));
             //t.Start();
             Byte[] sendBytes;
             string message;
             while (true)
             {
                 message = "Client" + (counter++).ToString();
                 lock (this)
                 {
                     sendBytes = Encoding.ASCII.GetBytes(message);
                     udpSendState.counter = counter;
                     udpSend.BeginSend(sendBytes, sendBytes.Length, new AsyncCallback(SendCallback), udpSendState);
                     sendDone.WaitOne();
                     Thread.Sleep(200);
                     ReceiveMessages();
                 }
             }
         }

         public void SendCallback(IAsyncResult iar)
         {
             UdpState udpState = iar.AsyncState as UdpState;
             if (iar.IsCompleted)
             {
                 Console.WriteLine("第{0}个发送完毕！", udpState.counter);
                 Console.WriteLine("number of bytes sent: {0}", udpState.udpClient.EndSend(iar));
                 //if (udpState.counter == 10)
                 //{
                 //    udpState.udpClient.Close();
                 //}
                 sendDone.Set();
             }
         }

         public void ReceiveMessages()
         {
             lock (this)
             {
                 udpReceive.BeginReceive(new AsyncCallback(ReceiveCallback), udpReceiveState);
                 receiveDone.WaitOne();
                 Thread.Sleep(100);
             }
         }
         public void ReceiveCallback(IAsyncResult iar)
         {
             UdpState udpState = iar.AsyncState as UdpState;
             if (iar.IsCompleted)
             {
                 Byte[] receiveBytes = udpState.udpClient.EndReceive(iar, ref udpReceiveState.ipEndPoint);
                 string receiveString = Encoding.Unicode.GetString(receiveBytes);
                 Console.WriteLine("Received: {0}", receiveString);
                 receiveDone.Set();
             }
         }

         public static void Main()
         {
             AsyncUdpClient auc = new AsyncUdpClient();
             auc.SendMsg();
             Console.Read();
         }
     }
 }

前天一个朋友让我帮忙写一个异步UDP通信的例子，于是参考了下MSDN修改了上面的代码，比较丑陋，主要是看看运行的功能。

后来准备把里面的UdpClient换成Socket来实现，但是碰到了个问题。但列文章写出来，共同探讨探讨。