public void Buttons_Click(object sender, EventArgs e)
        {
            // System.Windows.Forms.MessageBox.Show("You have clicked button " +
            //   ((System.Windows.Forms.Button)sender).Tag.ToString());
          
            String tnum = sender.ToString();
            int tlen = tnum.Length;
            String no = tnum.Substring(tlen - 1);
          
                if(no=="2")
                MessageBox.Show("" + no);
        }