设置文本框只能输入特定的符号

private void textBox1_KeyPress(object sender, KeyPressEventArgs e)
        {
            if (e.KeyChar >= 48 && e.KeyChar <= 57 || e.KeyChar == 8)
            {
            }
            else
            {
                e.Handled = true;
            }
        }

 

  private void db_PreviewTextInput(object sender, TextCompositionEventArgs e)
        {
            Regex re = new Regex("[^0-9.]+");
            e.Handled = re.IsMatch(e.Text);
        }