PHP reads xml example code_PHP tutorial

class xpathExtension{
public static function getNodes($domDoc, $xpathString) {
$xp = new DOMXPath($domDoc);
$xp->registerNamespace('x', 'http://www.w3.org/1999/xhtml');
$xp->registerNamespace('xhtml', 'http://www.w3.org/1999/xhtml');
$xp->registerNamespace('i18n', 'http://apache.org/cocoon/i18n/2.1');
$ret = array();
$nodes = $xp->query($xpathString);
foreach ($nodes as $node) {
array_push($ret, $node);
}
return $ret;
}
}
$domDoc = new DOMDocument();
$domDoc->load("x1.xml");
$xpathString = "//xml/products/product/description";
$domNodeList = xpathExtension::getNodes($domDoc, $xpathString);
//echo count($domNodeList);
foreach($domNodeList as $domNode){
echo $domNode->nodeValue;
}
?>

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