利用UDP进行信息传输

页面中控件两个textBox,(txtBox1,TbxMessage)一个button(btnSend)

//创建一个Thread实例  
        private Thread thread1;
        //创建一个UdpClient实例
        private UdpClient udpReceive;
        private UdpClient udpSend;
        private byte[] bytes;
        //private DialogResult result;
               
        public myUdpClient()
        {
            InitializeComponent();
        }
        private void myUdpClient_Load(object sender, EventArgs e)
        {
            thread1 = new Thread(new ThreadStart(ReceiveMessage));
            thread1.Start();
            this.textBox1.Text = "221.221.146.63";
        }
        private void BtnSend_Click(object sender, EventArgs e)
        {
            //初始化UdpClient
            udpSend = new UdpClient();
            //实际使用时应将127.0.0.1改为服务器的远程IP
            IPAddress remoteIPAddress = IPAddress.Parse(this.textBox1.Text.Trim());
            IPEndPoint remoteIPEndPoint = new IPEndPoint(remoteIPAddress, 8001);
            //将发送内容转换为字节数组
            byte[] bytes = System.Text.Encoding.UTF8.GetBytes(TbxMessage.Text);
            //设置重传次数
            int retry = 0;
            while (true)
            {
                try
                {
                    udpSend.Send(bytes, bytes.Length, remoteIPEndPoint);
                    break;
                }
                catch (SocketException se)
                {
                    if (retry < 3)
                    {
                        retry++; continue;
                    }
                    else
                    {
                        DialogResult result = MessageBox.Show("发送失败！");
                        break;
                    }
                }
            }
            //清空TbxMesage中的内容
            TbxMessage.Clear();
            //光标还原
            TbxMessage.Focus();
            //关闭UdpClient
        }
        private void ReceiveMessage()
        {
            //在本机指定的端口接收
            udpReceive = new UdpClient(8001);
            //将套接字加入组播组
            udpReceive.JoinMulticastGroup(IPAddress.Parse("224.100.0.10"), 50);
            //接收从远程主机发送过来的信息
            IPEndPoint iep= new IPEndPoint(IPAddress.Any, 0);
           while (true)
            {
                //ref表示引用类型的 IPPoint实例接收消息
          try
          {
                  bytes = udpReceive.Receive(ref iep);
          }
          catch(SocketException e)
          {
           DialogResult result = MessageBox.Show("发送失败！");
          }
                string str = Encoding.UTF8.GetString(bytes, 0, bytes.Length);
                string message = "来自" + iep.ToString() + "的消息";
                //显示消息 并以message为消息的标题
                DialogResult res = MessageBox.Show(str, message);
            }
        }
     

        private void myUdpClient_FormClosing(object sender, FormClosingEventArgs e)
        {
            //关闭连接
            udpReceive.Close();
            udpSend.Close();
            //终止线程
            thread1.Abort();
        }