phone-area-code-validator.php

<?php

  /**
  * Validates a 2-digit area code not composed by zeroes.
  * @link http://www.anatel.gov.br/legislacao/resolucoes/16-2001/383-resolucao-263.
  * @return bool
  */

  function validate (string $areaCode): bool
  {
    $areaCodes = array(
      '11', '12', '13', '14', '15', '16', '17', '18', '19', '21', '22', '24',
      '27', '28', '31', '32', '33', '34', '35', '37', '38', '41', '42', '43',
      '44', '45', '46', '47', '48', '49', '51', '53', '54', '55', '61', '62',
      '63', '64', '65', '66', '67', '68', '69', '71', '73', '74', '75', '77',
      '79', '81', '82', '83', '84', '85', '86', '87', '88', '89', '91', '92',
      '93', '94', '95', '96', '97', '98', '99'
    );

    $isValid = in_array($areaCode, $areaCodes);

    return $isValid;
  }