public static function addRow(DetailTable $table, $header, ?string $value, ?string $format = null): void
  {
    $date = \DateTime::createFromFormat('Y-m-d H:i:s', $value);

    if ($date)
    {
      // The $value is a valid datetime.      
      $table->addRow($header,
                     ['class'      => 'date',
                      'data-value' => $date->format('Y-m-d H:i:s')],
                     $date->format(($format) ? $format : self::$defaultFormat));
    }
    else
    {
      // The $value is not a valid datetime.
      $table->addRow($header, [], $value);
    }
  }