textbox color change when quantity is less

private void textBox2_TextChanged(object sender, EventArgs e)
{
  int quantity = 0;
  if (!Int32.TryParse(textBox2.Text, out quantity))
  {
    textBox2.BackColor = Color.Red;
    return;
  }

  if (quantity < 5)
    textBox2.BackColor = Color.Green;
  else
    textBox2.BackColor = Color.White;
}