C#的Socket实现UDP协议通信示例代码

privateIPEndPoint ipLocalPoint;

privateEndPoint RemotePoint;

privateSocket mySocket;

privateboolRunningFlag =false;

privatestringgetIPAddress()

 {

   // 获得本机局域网IP地址

   IPAddress[] AddressList = Dns.GetHostByName(Dns.GetHostName()).AddressList;

   if(AddressList.Length < 1)

   {

     return"";

   }

   returnAddressList[0].ToString();

 }

privateintgetValidPort(stringport)

  {

    intlport;

    //测试端口号是否有效

    try

    {

      //是否为空

      if(port =="")

      {

        thrownewArgumentException(

          "端口号无效，不能启动DUP");

      }

      lport = System.Convert.ToInt32(port);

    }

    catch(Exception e)

    {

      //ArgumentException, 

      //FormatException, 

      //OverflowException

      Console.WriteLine("无效的端口号："+ e.ToString());

      this.tbMsg.AppendText("无效的端口号："+ e.ToString() +"n");

      return-1;

    }

    returnlport;

  }

  privateIPAddress getValidIP(stringip)

  {

    IPAddress lip =null;

    //测试IP是否有效

    try

    {

      //是否为空

      if(!IPAddress.TryParse(ip,outlip))

      {

        thrownewArgumentException(

          "IP无效，不能启动DUP");

      }

    }

    catch(Exception e)

    {

      //ArgumentException, 

      //FormatException, 

      //OverflowException

      Console.WriteLine("无效的IP："+ e.ToString());

      this.tbMsg.AppendText("无效的IP："+ e.ToString() +"n");

      returnnull;

    }

    returnlip;

  }

//得到本机IP，设置UDP端口号  

ip = getValidIP(tbLocalIP.Text);

port = getValidPort(tbLocalPort.Text);

ipLocalPoint =newIPEndPoint(ip, port);

//定义网络类型，数据连接类型和网络协议UDP

mySocket =newSocket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);

//绑定网络地址

mySocket.Bind(ipLocalPoint);

//得到客户机IP

ip = getValidIP(tbRemoteIP.Text);

port = getValidPort(tbRemotePort.Text);

IPEndPoint ipep =newIPEndPoint(ip, port);

RemotePoint = (EndPoint)(ipep);

//启动一个新的线程，执行方法this.ReceiveHandle，

//以便在一个独立的进程中执行数据接收的操作

RunningFlag =true;

Thread thread =newThread(newThreadStart(this.ReceiveHandle));

thread.Start();

//定义一个委托

publicdelegatevoidMyInvoke(stringstrRecv);

privatevoidReceiveHandle()

{

  //接收数据处理线程

  stringmsg;

  byte[] data=newbyte[1024];

  MyInvoke myI =newMyInvoke(UpdateMsgTextBox);

  while(RunningFlag)

  {

    if(mySocket ==null|| mySocket.Available < 1)

    {

      Thread.Sleep(200);

      continue;

    }

    //跨线程调用控件

     //接收UDP数据报，引用参数RemotePoint获得源地址

     intrlen = mySocket.ReceiveFrom(data,refRemotePoint);

    msg = Encoding.Default.GetString(data, 0, rlen);

    tbMsg.BeginInvoke(myI,newobject[]{RemotePoint.ToString() +" : "+ msg});

  }

}

privatevoidbtSend_Click(objectsender, EventArgs e)

{

  stringmsg;

  msg = tbSendMsg.Text;

  //发送UDP数据包

  byte[] data = Encoding.Default.GetBytes(msg);

  mySocket.SendTo(data, data.Length, SocketFlags.None, RemotePoint);

}

privatevoidUpdateMsgTextBox(stringmsg)

{

  //接收数据显示

  this.tbMsg.AppendText( msg +"n");

}