public function validate(FormInterface $form) { if (!$form->isSynchronized()) { $form->addError(new FormError('The value is invalid')); } if (count($form->getExtraData()) > 0) { $form->addError(new FormError('This form should not contain extra fields')); } if ($form->isRoot() && isset($_SERVER['CONTENT_LENGTH'])) { $length = (int) $_SERVER['CONTENT_LENGTH']; $max = trim(ini_get('post_max_size')); switch (strtolower(substr($max, -1))) { // The 'G' modifier is available since PHP 5.1.0 case 'g': $max *= 1024; case 'm': $max *= 1024; case 'k': $max *= 1024; } if ($length > $max) { $form->addError(new FormError('The uploaded file was too large. Please try to upload a smaller file')); } } }