Question

All,

Trying to parse this SOAP response but xpath() is returning

Debug Warning: SimpleXMLElement::xpath() Undefined namespace prefix
Debug Warning: SimpleXMLElement::xpath() evaluation failed

 $result = '<?xml version="1.0" encoding="UTF-8"?>
<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/">
    <env:Header xmlns:env="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"/>
    <env:Body xmlns:env="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
        <v4:TrackReply xmlns:v4="http://fedex.com/ws/track/v4">
            ...
        </v4:TrackReply>
    </env:Body>
</soapenv:Envelope>';


 $xml = simplexml_load_string($result,NULL,NULL,'http://schemas.xmlsoap.org/soap/envelope/');



foreach($xml->xpath('env:Body') as $body){

    //drill down here...
}

Answer 1

Try registering the namespace to ‘env’

$xml->registerXPathNamespace('env', 'http://schemas.xmlsoap.org/soap/envelope/');

Edit
This code sets the namespace of child elements within body

$bodies = $xml->xpath('env:Body');
foreach($bodies as $body){
    $reply = $body->children('v4', TRUE)->TrackReply;
    var_dump($reply);
}

Alternatively, you can get an element like TrackReply directly with:

$xml->registerXPathNamespace('env', 'http://schemas.xmlsoap.org/soap/envelope/');
$xml->registerXPathNamespace('v4', 'http://fedex.com/ws/track/v4');
var_dump($xml->xpath('env:Body/v4:TrackReply'));