XML

$xml = new DOMDocument();
$xml->loadXML($doubanInfo);
//$element = $xml->childNodes->item(0);
$books = $xml->getElementsByTagNameNS('http://www.douban.com/xmlns/',"*");
//$element->removeAttributeNS('http://www.douban.com/xmlns/', 'db');
//print $xml->saveXML();
//var_dump($doubanInfo);
foreach( $books as $book)
{

 //$dbx= $book->getElementsByTagName("db:signature");
//echo $dbx->localName;
 // echo 'local name: ', $book->localName, ', prefix: ', $book->prefix, "\n";
echo $book->nodeValue;

}