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프로그램 설명

TcpListener와 TcpClient를 이용한 1:1 통신을 하는 프로그램입니다.

서버와 클라이언트 통신하는 순서와 아래와 같습니다.

실행 후

메시진 전송 후

프로그램 작성 순서

1. 서버 프로그램

    public partial class MainForm : Form
    {
        TcpListener serverSocket = null;
        TcpClient clientSocket = null;

        public MainForm()
        {
            InitializeComponent();

            // socket start
            new Thread(delegate()
                {
                    InitSocket();
                }).Start();
        }

        private void InitSocket()
        {
            try
            { 
                serverSocket = new TcpListener(IPAddress.Any, 9999);
                clientSocket = default(TcpClient);
                serverSocket.Start();
                DisplayText(" >> Server Started");

                clientSocket = serverSocket.AcceptTcpClient();
                DisplayText(" >> Accept connection from client");

                Thread threadHandler = new Thread(new ParameterizedThreadStart(OnAccepted));
                threadHandler.IsBackground = true;
                threadHandler.Start(clientSocket);
            }
            catch (SocketException se)
            {
                DisplayText(string.Format("InitSocket : SocketException : {0}", se.Message));
            }
            catch (Exception ex)
            {
                DisplayText(string.Format("InitSocket : Exception : {0}", ex.Message));
            }
        }

        private void OnAccepted(object sender)
        {
            TcpClient clientSocket = sender as TcpClient;

            while (true)
            {
                try
                {
                    NetworkStream stream = clientSocket.GetStream();
                    byte[] buffer = new byte[1024];

                    stream.Read(buffer, 0, buffer.Length);
                    string msg = Encoding.Unicode.GetString(buffer);
                    msg = msg.Substring(0, msg.IndexOf("$"));
                    DisplayText(" >> Data from client - " + msg);

                    string response = "Last Message from client - " + msg;
                    byte[] sbuffer = Encoding.Unicode.GetBytes(response);

                    stream.Write(sbuffer, 0, sbuffer.Length);
                    stream.Flush();

                    DisplayText(" >> " + response);
                }
                catch (SocketException se)
                {
                    DisplayText(string.Format("OnAccepted : SocketException : {0}", se.Message));
                    break;
                }
                catch (Exception ex)
                {
                    DisplayText(string.Format("OnAccepted : Exception : {0}", ex.Message));
                    break;
                }
            }

            clientSocket.Close();
        }

        private void DisplayText(string text)
        {
            if (richTextBoxMsg.InvokeRequired)
            {
                richTextBoxMsg.BeginInvoke(new MethodInvoker(delegate
                {
                    richTextBoxMsg.AppendText(text + Environment.NewLine);
                }));
            }
            else
                richTextBoxMsg.AppendText(text + Environment.NewLine);
 
        }

        private void MainForm_FormClosing(object sender, FormClosingEventArgs e)
        {
            if (clientSocket != null)
            { 
                clientSocket.Close();
                clientSocket = null;
            }

            if (serverSocket != null)
            {
                serverSocket.Stop();
                serverSocket = null;
            }
        }
    }

2. 클라이언트 프로그램

    public partial class MainForm : Form
    {
        TcpClient clientSocket = new TcpClient();

        public MainForm()
        {
            InitializeComponent();

            new Thread(delegate()
            {
                InitSocket();
            }).Start();      
        }

        private void InitSocket()
        {
            try
            { 
                clientSocket.Connect("192.168.0.12", 9999);
                DisplayText("Client Started");
                labelStatus.Text = "Client Socket Program - Server Connected ...";
            }
            catch (SocketException se) 
            {
                MessageBox.Show(se.Message, "Error");
            }
            catch (Exception ex) 
            {
                MessageBox.Show(ex.Message, "Error");
            }
        }
        
        private void btnSend_Click(object sender, EventArgs e)
        {
            NetworkStream stream = clientSocket.GetStream();
            byte[] sbuffer = Encoding.Unicode.GetBytes(richTextBox2.Text + "$");
            stream.Write(sbuffer, 0, sbuffer.Length);
            stream.Flush();

            byte[] rbuffer = new byte[1024];
            stream.Read(rbuffer, 0, rbuffer.Length);
            string msg = Encoding.Unicode.GetString(rbuffer);
            DisplayText(msg);

            richTextBox2.Text = "";
            richTextBox2.Focus();
        }

        private void MainForm_FormClosing(object sender, FormClosingEventArgs e)
        {
            if (clientSocket != null)
                clientSocket.Close();
        }

        private void DisplayText(string text)
        {
            if (richTextBox1.InvokeRequired)
            {
                richTextBox1.BeginInvoke(new MethodInvoker(delegate
                {
                    richTextBox1.AppendText(Environment.NewLine + " >> " + text);
                }));
            }
            else
                richTextBox1.AppendText(Environment.NewLine + " >> " + text);
        }
    }

프로그램 설명

msdn 에 있는 예제를 가지고 만든 버전입니다.

TcpListener 클래스 

http://msdn.microsoft.com/ko-kr/library/system.net.sockets.tcplistener(v=vs.110).aspx

TcpClient 클래스

http://msdn.microsoft.com/ko-kr/library/system.net.sockets.tcpclient(v=vs.110).aspx

클라이언트 버전은 사용자 입력을 반복적으로 입력받을 수 있게 수정했습니다.

클라이언트의 메시지를 서버가 받아서 대문자로 변경해 주는 작업만 처리합니다.

실행 후

메시지 전송 후

프로그램 작성 순서

1. 소켓/쓰레드과 관련한 네임스페이스를 서버/클라이언트 모두에 포함 시킵니다.

using System.Net;
using System.Net.Sockets;
using System.Threading;
using System.Diagnostics;

2. 서버 프로그램

        static void Main(string[] args)
        {
            TcpListener server = null;

            try
            {
                // Set the TcpListener on port 13000
                Int32 port = 14000;
                IPAddress localAddr = IPAddress.Parse("127.0.0.1");

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

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

                // Buffer for reading data
                byte[] bytes = new byte[256];
                string data = string.Empty;

                // Enter the listening loop
                while(true)
                {
                    Console.WriteLine("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 = string.Empty;

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

                    int bytesRead = 0;
                    // Loop to receive all the data sent by the client
                    while( (bytesRead=stream.Read(bytes, 0, bytes.Length)) != 0)
                    {
                        // Translate data bytes to a UTF8.
                        data = Encoding.UTF8.GetString(bytes, 0, bytesRead);
                        Console.WriteLine("Received: {0}", data);

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

                        byte[] msg = Encoding.UTF8.GetBytes(data);

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

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

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

3. 클라이언트 프로그램

        static void Main(string[] args)
        {
            string sendData = string.Empty;
            do
            {
                Console.Write("\n전송할 데이타를 입력해 주세요 : ");
                sendData = Console.ReadLine();

                if (!string.IsNullOrEmpty(sendData))
                    Connect("127.0.0.1", sendData);
            } while (sendData != "");
            
            Console.WriteLine("\nPress Enter to continue...");
            Console.Read();
        }

        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 = 14000;
                TcpClient client = new TcpClient(server, port);

                // Get a client stream for reading and writing
                // Stream stream = client.GetStream() : System.IO needs..
                NetworkStream stream = client.GetStream();

                // Translate the passed message into UTF8 and store it as Byte array.
                byte[] data = Encoding.UTF8.GetBytes(message);

                // 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;

                Int32 bytesRead = stream.Read(data, 0, data.Length);
                responseData = Encoding.UTF8.GetString(data, 0, bytesRead);
                Console.WriteLine("Received: {0}", responseData);

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