public function getFieldValidationOptions() { $fields = parent::getFieldValidationOptions(); $validEmailFields = EditableEmailField::get()->filter(array('ParentID' => (int) $this->ParentID))->exclude(array('ID' => (int) $this->ID)); $fields->add(DropdownField::create('EqualToID', _t('EditableConfirmEmailField.EQUALTO', 'Must be equal to'), $validEmailFields->map('ID', 'Title'), $this->EqualToID)->setEmptyString('- select -')); return $fields; }