/**
* Add preserve text element
*
* @param string $text
* @param mixed $fontStyle
* @param mixed $paragraphStyle
* @return PreserveText
*/
public function addPreserveText($text, $fontStyle = null, $paragraphStyle = null)
{
$this->checkValidity('preservetext');
$preserveText = new PreserveText(String::toUTF8($text), $fontStyle, $paragraphStyle);
$preserveText->setDocPart($this->getDocPart(), $this->getDocPartId());
$this->addElement($preserveText);
return $preserveText;
}
