function ISN_checksum_OK in ISBN Field 6

5 calls to ISN_checksum_OK()

generate_ISN_corrections in ./isbn.inc

ISBN_checksum_OK in ./isbn.inc

isbn_validate_10 in ./isbn.module

isbn_validate_8 in ./isbn.module

ISSN_checksum_OK in ./isbn.inc

File

./isbn.inc, line 104

Code

function ISN_checksum_OK($isn_proto, $length) {
  $isn_proto = ISN_clean($isn_proto);
  return strlen($isn_proto) == $length && bad_ISN_char_count($isn_proto) == 0 && mod11_checksum($isn_proto, $length) == 0;
}