UDP学习笔记（.NET）

以下代码来源于《C#网络编程技术教程》。

    public class UDPComm
    {
        public static byte[] EncodingASCII(string buf)//编码
        {
            byte[] data = Encoding.ASCII.GetBytes(buf + "
");
            return data;
        }
        public static string DecodingASCII(byte[] buf)//解码
        {
            string st = Encoding.ASCII.GetString(buf);
            return st;
        }
    }

class UDPServer
    {
        static UdpClient m_server;
        static ArrayList mblist;

        static void AddMember(IPEndPoint rep)//加入组
        {
            mblist.Add(rep);
            byte[] data = UDPComm.EncodingASCII("OK");
            m_server.Send(data, data.Length, rep);
        }
        static void DelMember(IPEndPoint rep)//离开组
        {
            mblist.Remove(rep);
            byte[] data = UDPComm.EncodingASCII("OK");
            m_server.Send(data, data.Length, rep);

        }
        static void SendToMember(string buf)//组内转发数据
        {
            foreach (IPEndPoint mb in mblist)
            {
                byte[] data = UDPComm.EncodingASCII(buf);
                m_server.Send(data, data.Length, mb);
            }
        }

        static void Main(string[] args)
        {
            string m_hostIP = "127.0.0.1";
            int m_port = 6666;
            IPEndPoint m_EndPoint;
            ArrayList memberlist = new ArrayList();
            bool rt = false;
            byte[] data;
            string m_ReturnData;

            //从命令行提取主机IP和端口
            if (args.Length < 2)
            {
                Console.WriteLine("Usage: UDPServer hostIP port");
            }
            else
            {
                m_hostIP = args[0].ToString();
                m_port = int.Parse(args[1].ToString());
                rt = true;
            }

            if (rt)
            {
                mblist = new ArrayList();//组成员列表

                IPAddress m_ipA = IPAddress.Parse(m_hostIP);
                m_EndPoint = new IPEndPoint(m_ipA, m_port);
                m_server = new UdpClient(m_EndPoint);

                Console.WriteLine("Ready for Connect......");
                while (true)
                {
                    data = m_server.Receive(ref m_EndPoint);//接收数据
                    m_ReturnData = UDPComm.DecodingASCII(data);

                    if (m_ReturnData.IndexOf("ADD") > -1)//加入组
                    {
                        AddMember(m_EndPoint);
                        Console.WriteLine(m_EndPoint.ToString() + "has added to group");
                    }
                    else if (m_ReturnData.IndexOf("DEL") > -1)//退出组
                    {
                        DelMember(m_EndPoint);
                        Console.WriteLine(m_EndPoint.ToString() + "has delete from group");
                    }
                    else
                    {
                        if (mblist.Contains(m_EndPoint))//转发数据
                        {
                            SendToMember(m_ReturnData + "[" + m_EndPoint.ToString() + "]");
                            Console.WriteLine(m_ReturnData + "[" + m_EndPoint.ToString() + "]"
                                + "has resented to member");
                        }
                    }
                }
                m_server.Close();
            }
        }
    }

class UDPClient
    {
        static void Main(string[] args)
        {
            string m_hostIP = "127.0.0.1";
            int m_port = 6666;
            UdpClient m_client;
            bool rt = false;
            byte[] data;
            string m_SendData, m_ReturnData;
            IPEndPoint m_EndPoint;

            //从命令行提取服务器地址和侦听端口
            if (args.Length < 2)
            {
                Console.WriteLine("Usage: UDPClient hostIP port");
            }
            else
            {
                m_hostIP = args[0].ToString();
                m_port = int.Parse(args[1].ToString());
                rt = true;
            }

            if (rt)
            {
                IPAddress m_ipA = IPAddress.Parse(m_hostIP);
                m_EndPoint = new IPEndPoint(m_ipA, m_port);

                IPAddress m_ipA1 = IPAddress.Parse("127.0.0.1");
                IPEndPoint m_EndPoint1 = new IPEndPoint(m_ipA1, 8060);
                //m_client = new UdpClient(); 不绑定本地终结点，系统将会随机分配一个终结点
                m_client = new UdpClient(m_EndPoint1);
                
                m_client.Connect(m_EndPoint);

                while (true)
                {
                    Console.WriteLine("Input [ADD|DEL|REF|QUIT|Message]:");
                    m_SendData = Console.ReadLine();

                    if(m_SendData.IndexOf("QUIT")>-1)//退出
                    {
                        m_SendData = "DEL";
                    }

                    if(m_SendData.IndexOf("REF")<=-1)//刷新显示
                    {
                        data = UDPComm.EncodingASCII(m_SendData);
                        m_client.Send(data, data.Length);
                    }
                    if (m_SendData.IndexOf("QUIT") > -1)
                        break;

                    data = m_client.Receive(ref m_EndPoint);
                    Console.WriteLine(m_EndPoint.ToString());
                    m_ReturnData = UDPComm.DecodingASCII(data);
                    Console.WriteLine(m_ReturnData);
                }
                //退出
                Console.WriteLine("Byte!");
                m_client.Close();
            }
        }
    }