addElement('text', 'string', array( 'label' => 'Search string', 'description' => $form->translate('The string you want to search for'), 'required' => true, )); $form->addElement('text', 'replacement', array( 'label' => 'Replacement', 'description' => $form->translate('Your replacement string'), )); } public function transform($value) { if ($value === null) { return null; } return str_replace( $this->getSetting('string'), $this->getSetting('replacement'), $value ); } }