System.Net.Sockets.Socket.Shutdown C# (CSharp) Method

        public void Shutdown(SocketShutdown how)
        {
            if (NetEventSource.IsEnabled) NetEventSource.Enter(this, how);
            if (CleanedUp)
            {
                throw new ObjectDisposedException(this.GetType().FullName);
            }

            if (NetEventSource.IsEnabled) NetEventSource.Info(this, $"how:{how}");

            // This can throw ObjectDisposedException.
            SocketError errorCode = SocketPal.Shutdown(_handle, _isConnected, _isDisconnected, how);

            if (NetEventSource.IsEnabled) NetEventSource.Info(this, $"Interop.Winsock.shutdown returns errorCode:{errorCode}");

            // Skip good cases: success, socket already closed.
            if (errorCode != SocketError.Success && errorCode != SocketError.NotSocket)
            {
                // Update the internal state of this socket according to the error before throwing.
                SocketException socketException = new SocketException((int)errorCode);
                UpdateStatusAfterSocketError(socketException);
                if (NetEventSource.IsEnabled) NetEventSource.Error(this, socketException);
                throw socketException;
            }

            SetToDisconnected();
            InternalSetBlocking(_willBlockInternal);
            if (NetEventSource.IsEnabled) NetEventSource.Exit(this);
        }

        static void Main(string[] args)
        {
            byte[] receiveBytes = new byte[1024];
            int port =8080;//服务器端口
            string host = "10.3.0.1";  //服务器ip
            
            IPAddress ip = IPAddress.Parse(host);
            IPEndPoint ipe = new IPEndPoint(ip, port);//把ip和端口转化为IPEndPoint实例 
            Console.WriteLine("Starting Creating Socket Object");
            Socket sender = new Socket(AddressFamily.InterNetwork, 
                                        SocketType.Stream, 
                                        ProtocolType.Tcp);//创建一个Socket 
            sender.Connect(ipe);//连接到服务器 
            string sendingMessage = "Hello World!";
            byte[] forwardingMessage = Encoding.ASCII.GetBytes(sendingMessage + "[FINAL]");
            sender.Send(forwardingMessage);
            int totalBytesReceived = sender.Receive(receiveBytes);
            Console.WriteLine("Message provided from server: {0}",
                              Encoding.ASCII.GetString(receiveBytes,0,totalBytesReceived));
            //byte[] bs = Encoding.ASCII.GetBytes(sendStr);

            sender.Shutdown(SocketShutdown.Both);  
            sender.Close();
            Console.ReadLine();
        }