cms.form.beforeSubmit

Triggered in Cms\Behaviors\FormComponent.

Fires before a form submission is saved, throw an exception to reject it.

Example usage:

Event::listen('cms.form.beforeSubmit', function ($component, $model) {
    if (SpamService::isSpam($model)) {
        throw new ValidationException(['content' => 'Submission rejected.']);
    }
});