C# UDP网络通信的实现示例

 // 先讲socket进行客户端和服务器的书写
 Socket socket;
 private void button1_Click(object sender, EventArgs e)
 {
     //参数1 ip地址类型 ipv4的类型
     //参数2 传递数据类型 数据报文类型
     //参数3 协议类型 udp协议
     //1 创建socket套接字作为服务器对象
     socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
     // 2绑定ip和端口
     IPAddress iPAddress = IPAddress.Parse("192.168.107.83");
     socket.Bind(new IPEndPoint(iPAddress,8081));
     //3 接受消息
     startReceive();
 }
    void startReceive()
  {
      //创建线程 开启线程
      new Thread(() =>
      {
          byte[] body = new byte[1024];
          while (true)
          {
              
              int count =   socket.Receive(body); //接受数据
              string s = Encoding.UTF8.GetString(body, 0, count);
              richTextBox1.Invoke((Action)(() =>
              {
                  richTextBox1.AppendText(s + "\t\n");
                  richTextBox1.SelectionStart=richTextBox1.Text.Length;
                  richTextBox1.ScrollToCaret();
              }));
          }

      }).Start() ;
  }    

//发消息的方法 给指定的人发消息
string[] ips = new string[] {"192.168.107.83",  };
private void button2_Click(object sender, EventArgs e)
{
    socket.SendTo(Encoding.UTF8.GetBytes(this.textBox1.Text),
        new IPEndPoint(IPAddress.Parse("192.168.107.83"), 8082)
        );
}

        public Form1()
        {
            InitializeComponent();
            
        }
        void f1()
        {
            byte[] body = new byte[1024];
            while (true)
            {
                int count = socket.Receive(body); //接受数据
                string s = Encoding.UTF8.GetString(body, 0, count);
                richTextBox1.Invoke((Action)(() =>
                {
                    richTextBox1.AppendText(s + "\t\n");
                    richTextBox1.SelectionStart = richTextBox1.Text.Length;
                    richTextBox1.ScrollToCaret();
                }));
            }
        }
        // 打开连接
        Socket socket;
        private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                //1创建客户端对象
                socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
                //bind 如果前后端写的端口一致的时候 出现错误，端口号只能使用一次
                //2 绑定ip和端口号
               socket.Bind(new IPEndPoint(IPAddress.Parse("192.168.107.83"), 8082));
                Thread th = new Thread(f1);
                th.Start();
            }
            catch (Exception ex)
            {
                MessageBox.Show("端口号被占用");
            }

        }

        //发送消息
        private void button2_Click(object sender, EventArgs e)
        {
          
            if (socket != null)
            {
              
                //参数1 发送的字符串转成字节数组
                //参数2 发送数据的远程终端 new IPEndPoint(IPAddress.Parse("192.168.107.83"), 8081)
                socket.SendTo(Encoding.UTF8.GetBytes("倒反天罡"), new IPEndPoint(IPAddress.Parse("192.168.107.83"), 8081));
           }
        }

        //关闭
        private void button3_Click(object sender, EventArgs e)
        {
            socket.Close();//关闭
            socket = null;
        }