TYPO3, Extbase: Formulardaten manuell validieren

Hier ein einfaches Beispiel, um eine Checkbox von einem Formular manuell zu validieren:

$arguments = $this->request->getArguments();
$validatorResolver = $this->objectManager->get('TYPO3\\CMS\\Extbase\\Validation\\ValidatorResolver');
$conjunctionValidator = $validatorResolver->createValidator('Conjunction');
$conjunctionValidator->addValidator($validatorResolver->createValidator('NotEmpty'));
$conjunctionValidator->addValidator($validatorResolver->createValidator('Boolean'));
$result = $conjunctionValidator->validate($arguments['agreelicenseterm']);

if ($result->hasErrors()) {
    // Benutzer wieder zurückschicken
    $this->addFlashMessage(LocalizationUtility::translate('must_agree_license_term',$this->extensionName), '', \TYPO3\CMS\Core\Messaging\FlashMessage::ERROR);
    $this->forward("license");
}