UDP用同一端口收发数据 c#

之前用UdpClient，发现当开了一个端口用于监听接收，则不能再用来发送（反之亦然）。这样对于简单的收发信息来说无问题，但如果需要nat穿透的程序，则变得困难。用Socket类则不存在该问题，参考下面示例代码：

    class Program
    {
        static void Main(string[] args)
        {
            SocketTest test = new SocketTest();
            test.StartReceive();
            Console.WriteLine("请输入对端口号，准备发送：");
            string port = Console.ReadLine();
            test.SendData(Encoding.UTF8.GetBytes("你好吗？"), IPAddress.Parse("127.0.0.1"), Convert.ToInt32(port));
            Console.ReadKey(true);
        }

        
    }

    public class SocketTest
    {
        private Socket _socket;
        IPEndPoint _local = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 5238);
        Thread _receiveThread = null;

        public void StartReceive()
        {
            _socket = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
            _receiveThread = new Thread(Receive);
            _receiveThread.Start();
        }

        public void SendData(byte[] data, IPAddress remoteIP, int remotePort)
        {
            _socket.SendTo(data, new IPEndPoint(remoteIP, remotePort));
        }

        public void Close()
        {
            if (_receiveThread != null)
                _receiveThread.Abort();
            if (_socket != null)
                _socket.Close();
        }

        private void Receive()
        {
            _socket.Bind(_local);
            Console.WriteLine("开始接收。。。");
            while (true)
            {
                byte[] buffer = new byte[1024];
                EndPoint remoteEP = (EndPoint)(new IPEndPoint(IPAddress.Any, 0));
                int len = _socket.ReceiveFrom(buffer, ref remoteEP);
                IPEndPoint ipEndPoint = remoteEP as IPEndPoint;
                Console.WriteLine("收到消息：客户机IP--{0}，，端口--{1}", ipEndPoint.Address.ToString(), ipEndPoint.Port.ToString());
                Console.WriteLine("消息内容：{0}", Encoding.UTF8.GetString(buffer, 0, len));
            }
        }

        
    }

转载： http://harvey8819.blog.163.com/blog/static/162365181201123121635983/