materio-base-d7/sites/all/modules/contrib/form/phone/include/phone.ca.inc

<?php

/**
 * @file
 * CCK Field for Canadian phone numbers.
 */

function phone_ca_metadata() {
  return array(
    'error' => '"%value" is not a valid North American phone number<br>North American Phone numbers should only contain numbers and + and - and ( and ) and spaces and be like 999-999-9999. Please enter a valid ten-digit phone number with optional extension.',
  );
}

/**
 * Verifies that $phonenumber is a valid ten-digit North American phone number
 *
 * @param string $phonenumber
 * @return boolean Returns boolean FALSE if the phone number is not valid.
 */

function valid_ca_phone_number($phonenumber) {

  $phonenumber = trim($phonenumber);

  // define regular expression
  $regex = '/
    \D*           # ignore non-digits
    (\d*)         # an optional 1
    \D*           # optional separator
    [2-9][0-8]\d  # area code (Allowed range of [2-9] for the first digit, [0-8] for the second, and [0-9] for the third digit)
    \D*           # optional separator
    [2-9]\d{2}    # 3-digit prefix (cannot start with 0 or 1)
    \D*           # optional separator
    \d{4}         # 4-digit line number
    \D*           # optional separator
    \d*           # optional extension
    \D*           # ignore trailing non-digits
    /x';
  // return true if valid, false otherwise
  $result = preg_match($regex, $phonenumber, $matches);
  return ($result && ($matches[1] == '' || $matches[1] == '1'));
}

/**
 * Convert a valid North American phone number into standard (444) 867-5309 x1234 format
 *
 * @param $phonenumber must be a valid ten-digit number (with optional extension)
 *
 */
function format_ca_phone_number($phonenumber, $field) {

  // define regular expression
  $regex = '/
    \D*            # ignore non-digits
    (\d*)          # an optional 1
    \D*            # optional separator
    ([2-9][0-8]\d) # area code (Allowed range of [2-9] for the first digit, [0-8] for the second, and [0-9] for the third digit)
    \D*            # optional separator
    ([2-9]\d{2})   # 3-digit prefix (cannot start with 0 or 1)
    \D*            # optional separator
    (\d{4})        # 4-digit line number
    \D*            # optional separator
    (\d*)          # optional extension
    \D*            # ignore trailing non-digits
    /x';

  // get digits of phone number
  preg_match($regex, $phonenumber, $matches);

  $separator = isset($field['ca_phone_separator']) ? $field['ca_phone_separator'] : '-';

  // construct ten-digit phone number
  $phonenumber =
    ( $field['ca_phone_parentheses'] ?
      '(' . $matches[2] . ') ' :
      $matches[2] . $separator ) .
      $matches[3] . $separator . $matches[4];

  // Optional extension
  if ($matches[5] != '') {
      $phonenumber .= ' x' . $matches[5];
  }

  if ($field['phone_country_code']) {
    // This condition check is pointless.  
    if ($matches[1] != '1') {
  	$phonenumber = '1' . ' ' . $phonenumber;
    }
  }
  return $phonenumber;
}