tcp.cs

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Net.NetworkInformation;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        TcpClient tcpClient = new TcpClient();
        NetworkStream networkStream = default(NetworkStream);
        string readData = null;

        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            connectTcp();
        }

        private void connectTcp()
        {
            Thread t = new Thread(getMessage);
            try
            {
                tcpClient = new TcpClient();
                tcpClient.Connect("127.0.0.1", 1234);
                t.Start();

            }
            catch (Exception ex)
            {
                t.Abort();
                tcpClient.Close();
                MessageBox.Show(ex.Message);
            }
        }

        private void getMessage()
        {
            string returnData;

            try
            {
                while (true)
                {
                    networkStream = tcpClient.GetStream();
                    var buffSize = tcpClient.ReceiveBufferSize;
                    byte[] inStream = new byte[buffSize];
                    networkStream.Read(inStream, 0, buffSize);

                    returnData = Encoding.ASCII.GetString(inStream);

                    readData = returnData;

                    invokeMsg();
                }
            }
            catch (Exception)
            {
                connectTcp();
            }
            
        }

        private void invokeMsg()
        {
            if (this.InvokeRequired)
            {
                this.Invoke(new MethodInvoker(invokeMsg));
            }
            else
            {
                textBox1.Text = readData;
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                byte[] outStream = Encoding.ASCII.GetBytes("Send data to server.");

                networkStream = tcpClient.GetStream();
                networkStream.Write(outStream, 0, outStream.Length);
                networkStream.Flush();
            }
            catch (Exception)
            {
                connectTcp();
            }

        }
    }
}