/**
* Overrides parent checkLength
*
* @param string $value Value
* @return boolean
*/
public function checkLength($value)
{
if (strlen($value) != 8) {
$this->setCheck(false);
} else {
$this->setCheck(true);
}
return parent::checkLength($value);
}
/**
* Validates the checksum
*
* @param string $value The barcode to check the checksum for
* @return boolean
*/
public function checksum($value)
{
if (strlen($value) == 8) {
$this->_checksum = '_issn';
} else {
$this->_checksum = '_gtin';
}
return parent::checksum($value);
}
/**
* Allows start and stop tag within checked chars
*
* @param string $value The barcode to check for allowed characters
* @return boolean
*/
public function checkChars($value)
{
if ($value[0] == '(') {
$value = substr($value, 1);
if ($value[strlen($value) - 1] == ')') {
$value = substr($value, 0, -1);
} else {
return false;
}
}
return parent::checkChars($value);
}