/** * Render the HTML element in the provided context * * @param array $context * * @return string The HTML string output */ public function render($context = []) { if ($element = $this->getElement()) { $class = $element->getAttribute('class', false); $class .= $class ? ' form-control' : 'form-control'; $this->getElement()->setAttribute('class', $class); } return parent::render($context); }