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 public void ShowMyPicture(string str1)
        {
            pictureBox1.Refresh();
            pictureBox1.Load(str1);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            MyDelegate delegate2 = new MyDelegate(ShowMyPicture);
            foreach(string str1 in listBox1.Items)
            {
                delegate2(str1);
                System.Threading.Thread.Sleep(1000);
            }