private function embedd_class($element, $class = null)
{
$html = 'class="' . esc_attr($this->get_default_class($element));
if (isset($class)) {
if (is_array($class)) {
$html .= ' ' . esc_attr(implode(' ', $class));
} else {
throw new rtFormInvalidArgumentsException('class [' . $element . ']');
}
}
$html .= '" ';
return $html;
}