服务器端

用TcpListener监听,接受TcpClient,以NetworkStream传输数据

public static void Main()
{
    TcpListener server = null;
    try
    {
        // Set the TcpListener on port 13000.
        Int32 port = 13000;
        IPAddress localAddr = IPAddress.Parse("127.0.0.1");

        // TcpListener server = new TcpListener(port);
        server = new TcpListener(localAddr, port);

        // Start listening for client requests.
        server.Start();

        // Buffer for reading data
        Byte[] bytes = new Byte[256];
        String data = null;

        // Enter the listening loop.
        while (true)
        {
            Console.Write("Waiting for a connection... ");

            // Perform a blocking call to accept requests.
            // You could also user server.AcceptSocket() here.
            TcpClient client = server.AcceptTcpClient();
            Console.WriteLine("Connected!");

            data = null;

            // Get a stream object for reading and writing
            NetworkStream stream = client.GetStream();

            int i;

            // Loop to receive all the data sent by the client.
            while ((i = stream.Read(bytes, 0, bytes.Length)) != 0)
            {
                // Translate data bytes to a ASCII string.
                data = System.Text.Encoding.ASCII.GetString(bytes, 0, i);
                Console.WriteLine("Received: {0}", data);

                // Process the data sent by the client.
                data = data.ToUpper();

                byte[] msg = System.Text.Encoding.ASCII.GetBytes(data);

                // Send back a response.
                stream.Write(msg, 0, msg.Length);
                Console.WriteLine("Sent: {0}", data);
            }

            // Shutdown and end connection
            client.Close();
        }
    }
    catch (SocketException e)
    {
        Console.WriteLine("SocketException: {0}", e);
    }
    finally
    {
        // Stop listening for new clients.
        server.Stop();
    }


    Console.WriteLine("\nHit enter to continue...");
    Console.Read();
}

客户端

static class Class1
{
    static void Connect(String server, String message)
    {
        try
        {
            // Create a TcpClient.
            // Note, for this client to work you need to have a TcpServer 
            // connected to the same address as specified by the server, port
            // combination.
            Int32 port = 13000;
            TcpClient client = new TcpClient(server, port);

            // Translate the passed message into ASCII and store it as a Byte array.
            Byte[] data = System.Text.Encoding.ASCII.GetBytes(message);

            // Get a client stream for reading and writing.
            //  Stream stream = client.GetStream();

            NetworkStream stream = client.GetStream();

            // Send the message to the connected TcpServer. 
            stream.Write(data, 0, data.Length);

            Console.WriteLine("Sent: {0}", message);

            // Receive the TcpServer.response.

            // Buffer to store the response bytes.
            data = new Byte[256];

            // String to store the response ASCII representation.
            String responseData = String.Empty;

            // Read the first batch of the TcpServer response bytes.
            Int32 bytes = stream.Read(data, 0, data.Length);
            responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes);
            Console.WriteLine("Received: {0}", responseData);

            // Close everything.
            stream.Close();
            client.Close();
        }
        catch (ArgumentNullException e)
        {
            Console.WriteLine("ArgumentNullException: {0}", e);
        }
        catch (SocketException e)
        {
            Console.WriteLine("SocketException: {0}", e);
        }

        Console.WriteLine("\n Press Enter to continue...");
        Console.Read();
    }
    public static void Main()
    {
        Connect("127.0.0.1", "hello");
    }
}