[Program C#] 서버-클라이언트 1:1 통신

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);
        }
    }