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

namespace Lab2_Exercice2
{
    public partial class Form1 : Form
    {
        private delegate void SafeCallDelegate(string text);

        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }


        private void button1_Click(object sender, EventArgs e)
        {
            Thread A = new Thread(new ThreadStart(PrintA));
            Thread B = new Thread(new ThreadStart(PrintB));
            Thread C = new Thread(new ThreadStart(PrintC));
            Thread D = new Thread(new ThreadStart(PrintD));
            Thread E = new Thread(new ThreadStart(PrintE));

            A.Start();
            B.Start();
            C.Start();
            D.Start();
            E.Start();
        }

        private void PrintA()
        {
            while (true)
            {
                AppendText("A");
                System.Threading.Thread.Sleep(100);
            }
        }

        private void PrintB()
        {
            while (true)
            {
                AppendText("B");
                System.Threading.Thread.Sleep(100);
            }
        }

        private void PrintC()
        {
            while (true)
            {
                AppendText("C");
                System.Threading.Thread.Sleep(100);
            }
        }

        private void PrintD()
        {
            while (true)
            {
                AppendText("D");
                System.Threading.Thread.Sleep(100);
            }
        }

        private void PrintE()
        {
            while (true)
            {
                AppendText("E");
                System.Threading.Thread.Sleep(100);
            }
        }

        private void AppendTextSafe(string text)
        {
            if (textBox1.InvokeRequired)
            {
                var d = new SafeCallDelegate(AppendTextSafe);
                textBox1.Invoke(d, new object[] { text });
            }
            else
            {
                textBox1.AppendText(text);
            }
        }


        private void AppendText(string text)
        {
            AppendTextSafe(text);
        }

    }
}