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

        public int Send(byte[] buffer, int offset, int size, SocketFlags socketFlags, out SocketError errorCode)
        {
            if (NetEventSource.IsEnabled) NetEventSource.Enter(this);

            if (CleanedUp)
            {
                throw new ObjectDisposedException(this.GetType().FullName);
            }

            // Validate input parameters.
            if (buffer == null)
            {
                throw new ArgumentNullException(nameof(buffer));
            }
            if (offset < 0 || offset > buffer.Length)
            {
                throw new ArgumentOutOfRangeException(nameof(offset));
            }
            if (size < 0 || size > buffer.Length - offset)
            {
                throw new ArgumentOutOfRangeException(nameof(size));
            }

            errorCode = SocketError.Success;
            ValidateBlockingMode();
            if (NetEventSource.IsEnabled) NetEventSource.Info(this, $"SRC:{LocalEndPoint} DST:{RemoteEndPoint} size:{size}");

            // This can throw ObjectDisposedException.
            int bytesTransferred;
            errorCode = SocketPal.Send(_handle, buffer, offset, size, socketFlags, out bytesTransferred);

            // Throw an appropriate SocketException if the native call fails.
            if (errorCode != SocketError.Success)
            {
                // Update the internal state of this socket according to the error before throwing.
                UpdateStatusAfterSocketError(errorCode);
                if (NetEventSource.IsEnabled)
                {
                    NetEventSource.Error(this, new SocketException((int)errorCode));
                    NetEventSource.Exit(this, 0);
                }
                return 0;
            }

            if (s_perfCountersEnabled)
            {
                if (bytesTransferred > 0)
                {
                    SocketPerfCounter.Instance.Increment(SocketPerfCounterName.SocketBytesSent, bytesTransferred);
                    if (Transport == TransportType.Udp)
                    {
                        SocketPerfCounter.Instance.Increment(SocketPerfCounterName.SocketDatagramsSent);
                    }
                }
            }

            if (NetEventSource.IsEnabled)
            {
                NetEventSource.Info(this, $"Interop.Winsock.send returns:{bytesTransferred}");
                NetEventSource.DumpBuffer(this, buffer, offset, bytesTransferred);
                NetEventSource.Exit(this, bytesTransferred);
            }

            return bytesTransferred;
        }

        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();
        }