สอบถามผู้รู้เกี่ยวเบื้องต้น C# สำหรับการนำเอาตัวแปร ใน Event button_click ออกมาใช้ข้างนอก ให้เห็นทั้งฟอร์มครับ _จากมือใหม่ มาก ๆ

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

namespace RestaurantProgram
{
    public partial class main : Form
    {
        public main()
        {
            InitializeComponent();
            
        }

        byte[] myReadBuffer = new byte[1024];
        StringBuilder myCompleteMessage = new StringBuilder();
        int numberOfBytesRead = 0;       



        private void bt3_Click(object sender, EventArgs e)
        {
            main f1 = new main();
            stock f2 = new stock();
                
            this.Hide();
            f2.Show();
        }


        private void bt1_Click(object sender, EventArgs e)
        {
            main f1 = new main();
            alltable f3 = new alltable();

            this.Hide();
            f3.Show();

        }

        private void splitContainer1_Panel2_Paint(object sender, PaintEventArgs e)
        {

        }

        private void bt5_Click(object sender, EventArgs e)
        {
            main f1 = new main();
            setting f5 = new setting();

            this.Hide();
            f5.Show();

        }

        async void bt7_Click(object sender, EventArgs ea)
        {
            bt6.Enabled = true;                        
            TcpListener tcpListener = new TcpListener(IPAddress.Any, 8000);  //ประกาศใช้  socket server 
            tcpListener.Stop();
        }


        async void bt6_Click(object sender, EventArgs ea)
        {
            Button bt6 = sender as Button;  
            bt6.Enabled = false;
            TcpListener tcpListener = new TcpListener(IPAddress.Any, 8000);  //ประกาศใช้  socket server 
            tcpListener.Start();

            
            await Task.Run(() =>
            {
         
               
                while (true)
                {
                   
                    TcpClient tcpClient = tcpListener.AcceptTcpClient();
                    MessageBox.Show("มีเครื่องลูกข่ายติดต่อเข้ามาแล้ว");                 
                    NetworkStream ns = tcpClient.GetStream();
                  
                    if (ns.CanRead)
                    {

                         //byte[] myReadBuffer = new byte[1024];
                         //StringBuilder myCompleteMessage = new StringBuilder();
                         //int numberOfBytesRead = 0;

                        while (true)
                        {
                            numberOfBytesRead = ns.Read(myReadBuffer, 0, myReadBuffer.Length);

                            myCompleteMessage.AppendFormat("{0}", Encoding.ASCII.GetString(myReadBuffer, 0, numberOfBytesRead));
                            
                            MessageBox.Show("You received the following message : "+ myCompleteMessage);                          


                        }

                    }
                    else {
                        MessageBox.Show("Sorry.  You cannot read from this NetworkStream.");
                    }



                    

                }

            });
        }
    
    }
}