public function addHtmlFragment($content, $charset = 'UTF-8')
{
$d = new \DOMDocument('1.0', $charset);
$root = $d->appendChild($d->createElement(self::FRAGMENT_ROOT_TAGNAME));
$bodynode = Helpers::getBodyNodeFromHtmlFragment($content, $charset);
foreach ($bodynode->childNodes as $child) {
$inode = $root->appendChild($d->importNode($child, true));
if ($inode) {
$this->addNode($inode);
}
}
}
