src/RijksregisternummerHelper.php
/**
   * Extract the raw year, month, and day of the birthday of an identification number of the National Register.
   *
   * @param string $rijksregisternummer The clean and valid identification number of the National Register.
   *
   * @return array
   */
Extract the raw year, month, and day of the birthday of an identification number of the National Register.
@param string $rijksregisternummer The clean and valid identification number of the National Register.

@return array
Extract the raw year month and day of the birthday of an identification number of the National Register . @param string $rijksregisternummer The clean and valid identification number of the National Register . @return array
private static function extractBirthdayParts(string $rijksregisternummer): array
  {
    $part1 = substr($rijksregisternummer, 0, 9);
    $part2 = substr($rijksregisternummer, 9, 2);
    $check    = 97 - (((int)$part1) % 97);
    $born1900 = ($check==$part2);
    $year  = (($born1900) ? '19' : '20').substr($rijksregisternummer, 0, 2);
    $month = (int)substr($rijksregisternummer, 2, 2);
    $day   = (int)substr($rijksregisternummer, 4, 2);
    return [$year, $month, $day];
  }
private static function extractBirthdayParts ( string $ rijksregisternummer ) : array { $ part1 = substr ( $ rijksregisternummer , 0 , 9 ) ; $ part2 = substr ( $ rijksregisternummer , 9 , 2 ) ; $ check = 97 - ( ( ( int ) $ part1 ) % 97 ) ; $ born1900 = ( $ check == $ part2 ) ; $ year = ( ( $ born1900 ) ? '19' : '20' ) . substr ( $ rijksregisternummer , 0 , 2 ) ; $ month = ( int ) substr ( $ rijksregisternummer , 2 , 2 ) ; $ day = ( int ) substr ( $ rijksregisternummer , 4 , 2 ) ; return [ $ year , $ month , $ day ] ; }
Extract the raw year, month, and day of the birthday of an identification number of the National Register.
Extract the raw year month and day of the birthday of an identification number of the National Register .