namespace TestTask
{
    public partial class Form1 : Form
    {
        public delegate void SetTextBox(string s);
        public SetTextBox setText_delegate;
        
        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Main1();
        }

        public void SetTextCall(string s)
        { 
            textBox1.Text=s;
        }

        public async void Main1()
           {
              var tasks = new List<Task>();
              Random rnd = new Random();
              Object lockObj = new Object();
              String[] words6 = { "reason", "editor", "rioter", "rental",
                                  "senior", "regain", "ordain", "rained" };

              foreach (var word6 in words6)
                 tasks.Add(Task.Factory.StartNew( (word) => { Char[] chars = word.ToString().ToCharArray();
                                                              double[] order = new double[chars.Length];
                                                              lock (lockObj) {
                                                                 for (int ctr = 0; ctr < order.Length; ctr++)
                                                                     order[ctr] = rnd.NextDouble();
                                                              }
                                                              Array.Sort(order, chars);
                                                              setText_delegate(word6);
                                                              //Console.WriteLine("{0} --> {1}", word,
                                                              //                  new String(chars));
                                                            }, word6));

              Task.WaitAll(tasks.ToArray());
           }

        private void Form1_Load(object sender, EventArgs e)
        {
            setText_delegate = new SetTextBox(SetTextCall);
        }

    }
}