Method for C# to perform asynchronous communication based on UDP

using System;
using ;
using ;
using ;
using ;
using ;
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(, listenPort);
   remoteEP = new IPEndPoint((())[0], remotePort);
   udpReceive = new UdpClient(ipEndPoint);
   udpSend = new UdpClient();
   udpReceiveState = new UdpState();   
    = udpReceive;
    = ipEndPoint;
   udpSendState = new UdpState();
    = udpSend;
    = remoteEP;
  }
  public void ReceiveMsg()
  {
   ("listening for messages");
   while(true)
   {
    lock (this)
    { 
     IAsyncResult iar = (new AsyncCallback(ReceiveCallback), udpReceiveState);
     ();
     (100);
    }
   }
  }
  private void ReceiveCallback(IAsyncResult iar)
  {
   UdpState udpReceiveState =  as UdpState;
   if ()
   {
    Byte[] receiveBytes = (iar, ref );
    string receiveString = (receiveBytes);
    ("Received: {0}", receiveString);
    //(100);
    ();
    SendMsg();
   }
  }
  private void SendMsg()
  {
   ();
    = udpSend;
    ++;
   string message = ("The{0}indivualUDPRequest processing is completed！",);
   Byte[] sendBytes = (message);
   (sendBytes, , new AsyncCallback(SendCallback), udpSendState);
   ();
  }
  private void SendCallback(IAsyncResult iar)
  {
   UdpState udpState =  as UdpState;
   ("The{0}indivual请求处理完毕！", );
   ("number of bytes sent: {0}", (iar));
   ();
  }
  public static void Main()
  {
   AsyncUdpSever aus = new AsyncUdpSever();
   Thread t = new Thread(new ThreadStart());
   ();
   ();
  }
 }
}

using System;
using ;
using ;
using ;
using ;
using ;
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(, listenPort);
   remoteEP = new IPEndPoint((())[0],remotePort);
   udpReceive = new UdpClient(localEP);   
   udpSend = new UdpClient();
   udpSendState = new UdpState();
    = remoteEP;
    = udpSend;
   udpReceiveState = new UdpState();
    = remoteEP;
    = udpReceive;
   receiveSocket = new Socket(, , );
   (localEP);
   sendSocket = new Socket(, , );
   (remoteEP);
  }
  public void SendMsg()
  { 
   (remoteEP);
   //Thread t = new Thread(new ThreadStart(ReceiveMessages));
   //();
   Byte[] sendBytes;
   string message;   
   while (true)
   { 
    message = "Client" + (counter++).ToString();
    lock (this)
    {
     sendBytes = (message);
      = counter;
     (sendBytes, , new AsyncCallback(SendCallback), udpSendState);
     ();
     (200);
     ReceiveMessages();
    }
   }    
  }
  public void SendCallback(IAsyncResult iar)
  {
   UdpState udpState =  as UdpState;
   if ()
   {
    ("The{0}All sent！", );
    ("number of bytes sent: {0}", (iar));
    //if ( == 10)
    //{
    // ();
    //}
    ();
   }   
  }
  public void ReceiveMessages()
  {
   lock (this)
   {
    (new AsyncCallback(ReceiveCallback), udpReceiveState);
    ();
    (100);
   } 
  }
  public void ReceiveCallback(IAsyncResult iar)
  {
   UdpState udpState =  as UdpState;
   if ()
   {
    Byte[] receiveBytes = (iar, ref );
    string receiveString = (receiveBytes);
    ("Received: {0}", receiveString);
    ();
   }   
  }
  public static void Main()
  {
   AsyncUdpClient auc = new AsyncUdpClient();
   ();
   ();
  }
 }
}