cristobal/01_validate_orgnr.php

## 01_validate_orgnr.php
<?php

/**
 * Validate orgnr
 *  Validates an string number according to the brreg spec
 * 	https://www.brreg.no/om-oss/oppgavene-vare/alle-registrene-vare/om-enhetsregisteret/organisasjonsnummeret/
 *
 * Test case: https://repl.it/repls/TechnicalForcefulBsddaemon
 *
 * @param <string> $value
 */
function validate_orgnr($value) {
  if (!preg_match("/^\d{9}$/", $value, $matches)) {
    throw new \Exception("Value must be a sequence of 9 numbers (value: {$value})");
  }

  $numbers = array_map(
    function ($value) { return intval($value); },
    str_split($matches[0])
  );

  $weights = array( 3, 2, 7, 6, 5, 4, 3, 2 );
  $products = array_map(
    function ($weight, $index) use($numbers) { return $numbers[$index] * $weight; },
    $weights,
    array_keys($weights)
  );

  $sum = array_reduce(
    $products,
    function ($acc, $product) { return $acc + $product; },
    0
  );

  $mod11 = 11;
  $rem = $sum % $mod11;
  $cn = $rem == 0
    ? 0
    : $mod11 - $rem;

  if ($cn >= 10) {
    return false;
  }

  return $cn === $numbers[8];
}

## 02_validate_orgnr.js
/**
 * Validate orgnr
 *  Validates an string number according to the brreg spec
 * 	https://www.brreg.no/om-oss/oppgavene-vare/alle-registrene-vare/om-enhetsregisteret/organisasjonsnummeret/
 *
 *  Test case https://repl.it/@cristobal1/HappyVengefulDiscussion
 *
 * @param {string} value
 */
function validate_orgnr (value) {
  const pattern = /^\d{9}$/
  if (!pattern.test(value)) {
    throw new Error(`Value must be a sequence of 9 numbers (value: ${value})`)
  }

  const numbers = String(value).split('').map(value => Number(value))
  const weights = [ 3, 2, 7, 6, 5, 4, 3, 2 ]
  const products = weights.map((value, index) => numbers[index] * value)
  const sum = products.reduce((acc, product) => acc + product, 0)

  const mod11 = 11
  const rem = sum % mod11
  const cn = rem === 0
    ? 0
    : mod11 - rem

  if (cn >= 10) {
    return false
  }

  return cn === numbers[8]
}
	<?php

	/**
	* Validate orgnr
	* Validates an string number according to the brreg spec
	* https://www.brreg.no/om-oss/oppgavene-vare/alle-registrene-vare/om-enhetsregisteret/organisasjonsnummeret/
	*
	* Test case: https://repl.it/repls/TechnicalForcefulBsddaemon
	*
	* @param <string> $value
	*/
	function validate_orgnr($value) {
	if (!preg_match("/^\d{9}$/", $value, $matches)) {
	throw new \Exception("Value must be a sequence of 9 numbers (value: {$value})");
	}

	$numbers = array_map(
	function ($value) { return intval($value); },
	str_split($matches[0])
	);

	$weights = array( 3, 2, 7, 6, 5, 4, 3, 2 );
	$products = array_map(
	function ($weight, $index) use($numbers) { return $numbers[$index] * $weight; },
	$weights,
	array_keys($weights)
	);

	$sum = array_reduce(
	$products,
	function ($acc, $product) { return $acc + $product; },
	0
	);

	$mod11 = 11;
	$rem = $sum % $mod11;
	$cn = $rem == 0
	? 0
	: $mod11 - $rem;

	if ($cn >= 10) {
	return false;
	}

	return $cn === $numbers[8];
	}