PHP Query XML with xPath - php

Question

I have an XML Structure like the following:
<Tickets>
<EventsPoints>
<Event ID="23">
<PerformanceName>U2</PerformanceName>
<EventDate>25/05/2012</EventDate>
<EventPrice>75.00</EventPrice>
</Event>
<Event ID="27">
<PerformanceName>Jedward</PerformanceName>
<EventDate>28/05/2012</EventDate>
<EventPrice>20.00</EventPrice>
</Event>
<Event ID="27">
<PerformanceName>Rolling Stones</PerformanceName>
<EventDate>03/12/2012</EventDate>
<EventPrice>80.00</EventPrice>
</Event>
</EventsPoints>
</Tickets>
Basically I want to search this XML for a certain performance name, say "U2", and then return that entire XML block (i.e. that performance name, event date and price - all in formatted XML and saved in a separate xml file)
This is my php code but it doesn't seem to be extracting the data correctly:
$srcDom = new DOMDocument;
$srcDom->load('/var/www/html/xml/searchfile.xml');
$xPath = new DOMXPath($srcDom);
foreach ($srcDom->getElementsByTagName('Event') as $event) {
$dstDom = new DOMDocument('1.0', 'utf-8');
$dstDom->appendChild($dstDom->createElement('EventsPricePoints'));
$dstDom->documentElement->appendChild($dstDom->importNode($event, true));
$allEventsForVenue = $xPath->query(
sprintf(
'/Tickets/EventsPoints/Event/PerformanceName[.="U2"]'
)
);
foreach ($allEventsForVenue as $event) {
$dstDom->documentElement->appendChild($dstDom->importNode($event, true));
}
$dstDom->formatOutput = true;
$dstDom->save(sprintf('/var/www/html/xml/searchresults1.xml'));
}

Answer 1

Your XPath gets the PerformanceName element when you want the parent element. Change it to
/Tickets/EventsPoints/Event/PerformanceName[.="U2"]/..
or
/Tickets/EventsPoints/Event[PerformanceName[.="U2"]]
or import
$event->parentNode
Also, you dont need the first foreach. Remove it and move the code writing the $dstDom into the code iterating the XPath result. See http://codepad.org/zfOZXycZ
Also see:
DOMDocument in php and
http://schlitt.info/opensource/blog/0704_xpath.html