public  class TCPIPServer
    {
        #region 成員
        private static TCPIPServer tcpIPServer;
        private static Socket socket;
        #endregion
        #region 屬性

        #endregion
        #region 方法
        /// <summary>
        /// 建立伺服器
        /// </summary>
        /// <param name="port"></param>
        /// <returns></returns>
        public static TCPIPServer CreateServer(int port)
        {
            if (tcpIPServer == null && socket == null)
            {
                return tcpIPServer = new TCPIPServer(port);
            }
            return tcpIPServer;
        }
        private TCPIPServer(int port)
        {
            socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            IPEndPoint ipEndPoint = new IPEndPoint(IPAddress.Any, port);
            socket.Bind(ipEndPoint);
            socket.Listen(10);
            BeginAccept(socket);
        }
        /// <summary>
        /// TCPIP訊息事件
        /// </summary>
        public event EventHandler<ClientInfoEvent> TcpMsgEvent;
        /// <summary>
        /// TCPIP登陸事件(不支援獲取TCPIP資料)
        /// </summary>
        public event EventHandler<ClientInfoEvent> TcpClientInfoEvent;
        private Dictionary<string, Socket> ConnectionList = new Dictionary<string, Socket>();
        private void BeginAccept(Socket objsocket)
        {
            objsocket.BeginAccept(callback=> {
              var client=  objsocket.EndAccept(callback);
              var ip = client.RemoteEndPoint.ToString();
                if (!ConnectionList.ContainsKey(ip))
                {
                    ConnectionList.Add(ip,client);
                    TcpClientInfoEvent?.Invoke(tcpIPServer,new ClientInfoEvent(ConnectionList));
                }
                BeginReceive(client,0);
                BeginAccept(objsocket);
            },null);
        }
        private void BeginReceive(Socket objsocket,int num)
        {
            byte[] buffer = new byte[4096];
            objsocket.BeginReceive(buffer,0,buffer.Length,SocketFlags.None,callback=> 
            {
              var length=  objsocket.EndReceive(callback);
                if (length>0)
                {
                    var bytes = new byte[length];
                    Array.Copy(buffer,bytes,length);
                    TcpMsgEvent?.Invoke(tcpIPServer,new ClientInfoEvent(new UdpReceiveResult(bytes,objsocket.RemoteEndPoint as IPEndPoint), ConnectionList));
                    num = 0;
                    BeginReceive(objsocket, num);
                }
                else if(length==0)//就是我length=0就是斷開了
                {
                   ConnectionList.Remove(objsocket.RemoteEndPoint.ToString());
                   objsocket.Dispose();
                }
            },null);
        }
        public void Send(byte[] buffer, EndPoint endpoint)
        {
            ConnectionList[endpoint.ToString()].BeginSend(buffer,0,buffer.Length,SocketFlags.None,callback=> 
            {
                ConnectionList[endpoint.ToString()].EndSend(callback);
            },null);
        }
        #endregion
    }