Someone

        private void btnpd_Click(object sender, EventArgs e)
        {
            int x;
            bool y;
            y = true;
            x = 1;
            while (x <= editAnswr.Text.Length)
            {
                if (editAnswr.Text.Substring(x - 1, 1) == ".")
                {
                    y = false;
                }
                x++;
            }
            if (y == true)
            {
                editAnswr.Text = editAnswr.Text + ".";
            }
        }