Problem with 'undefined namespace prefix' with XPath in PHP?

Question

Very new to PHP/programming in general, and I've been trying to run a PHP file set up to parse an Atom feed outputted from the Google Search API for Shopping. When run however, the code outputs a large number enter code heref errors (warnings), all having to do with XPath:

Warning: SimpleXMLElement::xpath() [simplexmlelement.xpath]: Undefined namespace prefix in /home/ultradea/public_html/gtest/search.php on line 205

Warning: SimpleXMLElement::xpath() [simplexmlelement.xpath]: xmlXPathEval: evaluation failed in /home/ultradea/public_html/gtest/search.php on line 205

Warning: Invalid argument supplied for foreach() in /home6/legionit/public_html/pricemash/search.php on line 289

The full code I'm working with can be found here: search.php

Here's the uploaded copy I'm working with that outputs the errors - http://ultra-deals.com/gtest/search.php

And here's the specific code in question

Lines 204-207
$xml = simplexml_load_string($return);
$result = $xml->xpath('//openSearch:totalResults');
$START = array_shift($xml->xpath('openSearch:startIndex'));
$RESULTS = array_shift($xml->xpath('openSearch:totalResults'));
<...> Line 261
$spelling_suggestion = array_shift($xml->xpath('s:spelling/s:suggestion'));
<...> Lines 273-280
$promos = "";
foreach ($xml->xpath('s:promotions/*') as $item) {
   $promos .= "<td><a href='$item[link]'>$item[description]";
   if ($item[imageLink] != "") {
     $promos .= "<br/><img src='$item[imageLink]'>";
   }
   $promos .= "</td>";
}
<...> Lines 328-335
$NARROW = "";
foreach ($xml->xpath('s:facets/*') as $item) {
 $values = $item->xpath('s:bucket');
 $type = $item['type'];
 $attrib_name = $item['name'];
 if ($attrib_name == "") {
   $attrib_name = $item['property'];  // Default types
 }

Each of those correspond to one or more of the error messages outputted on the search.php file I uploaded to my server. I have no experience with XPath, so I'm not even exactly sure what the namespace prefix in question is. Really appreciate the help!

Answer 1

openSearch is the undefined namespace here. You'll have to define that earlier, and everything should start working properly.

Answer 2

您应该考虑使用XQuery PHP扩展来解决您的问题： http : //www.zorba-xquery.com/site2/html/php.html