(PHP 4)
xpath_eval_expression — Evaluates the XPath Location Path in the given string
Example #1 xpath_eval_expression() Example
<?php
include("example.inc");
if (!$dom = domxml_open_mem($xmlstr)) {
    echo "Error while parsing the document\n";
    exit;
}
$xpath = xpath_new_context($dom);
var_dump(xpath_eval_expression($xpath, '/chapter/@language'));
?>
The above example will output:
object(XPathObject)(2) {
   ["type"]=>
   int(1)
   ["nodeset"]=>
   array(1) {
     [0]=>
     object(domattribute)(5) {
       ["type"]=>
       int(2)
       ["name"]=>
       string(8) "language"
       ["value"]=>
       string(2) "en"
       [0]=>
       int(7)
       [1]=>
       int(138004256)
     }
  }
}
See also xpath_eval().