PHP - Get value of XML node

Question

I have an XML file like so:

<?xml version="1.0" encoding="UTF-8"?>
<GeteBayDetailsResponse xmlns="urn:ebay:apis:eBLBaseComponents">
  <Timestamp>2012-07-04T13:54:51.873Z</Timestamp>
  <Ack>Success</Ack>
  <Version>779</Version>
  <Build>E779_CORE_BUNDLED_14986049_R1</Build>
  <SiteDetails>
    <Site>US</Site>
    <SiteID>0</SiteID>
    <DetailVersion>1</DetailVersion>
    <UpdateTime>2009-07-09T10:48:17.000Z</UpdateTime>
  </SiteDetails>
  <SiteDetails>
    <Site>Canada</Site>
    <SiteID>2</SiteID>
    <DetailVersion>1</DetailVersion>
    <UpdateTime>2009-07-09T10:48:17.000Z</UpdateTime>
  </SiteDetails>
</GeteBayDetailsResponse>

I am trying to find a way to get the value of the SiteID node where the Site node equals whatever.

I have tried using XPath and DomDocument functions but without any luck. Some of the messed up code is below:

    $xml_file ='SiteDetails.xml';
    $xmlDoc = new DomDocument();
    $xmlDoc->load($xml_file);
    $xpath = new DOMXpath($xmlDoc);

    $xpath->registerNamespace('ebay', 'urn:ebay:apis:eBLBaseComponents');

    //$siteIDList = $xpath->query("/ebay:GeteBayDetailsResponse/ebay:SiteDetails[ebay:Site='UK']/ebay:SiteID");
    //$siteIDList =  $xpath->query("/GeteBayDetailsResponse/SiteDetails[Site=\"UK\"]/SiteID");

//$siteIDList =  $xpath->query("//*[namespace-uri()='urn:ebay:apis:eBLBaseComponents' and name()='Site' and text()='$site']/following-sibling::*[namespace-uri()='urn:ebay:apis:eBLBaseComponents' and name()='SiteID']/text()");

    //var_dump($siteIDList);
    //echo $siteIDList->item(0)->nodeValue;

            /*$SiteDetails = $xmlDoc->getElementsByTagName('SiteDetails');
            $count = 0;
            foreach($SiteDetails as $details){
            //  print_r($details);
            echo $details->nodeValue;
                if ($details->nodeValue == $site){
                    echo 'YEAH';
                    echo $details->SiteID;
                }
            $count ++;  
            }*/
            //$siteID = $siteIDNode->item(8)->nodeValue;        

    //var_dump($siteIDNode);
}

Can anyone help? As you can see from the above, I am confused...

Answer 1

The general idea is that you iterate over each SiteDetails node and check the Site node value against the value you are looking for.

Assuming $xml contains your xml as SimpleXML instance

$site = 'Canada';
$siteId = null;

foreach($xml->SiteDetails as $sd) {
  if(((string)$sd->Site) === $site) {
    $siteId = (int)$sd->SiteID;
    //break;
  }
}

var_dump($siteId); //int(2)

Here is a working example on codepad

Solution using xpath()

Here is a solution using xpath()

$xml->registerXPathNamespace('ebay','urn:ebay:apis:eBLBaseComponents');
$site = 'Canada';
$siteId = $xml->xpath('ebay:SiteDetails/ebay:Site[text()="'.$site.'"]/../ebay:SiteID');
echo (string)$siteId[0]; //2

working example in codepad

Explanation:

1. First we find SiteDetails node with child node Site with value "Canada" (or any other value in $site) by using text() function of xpath which returns the value of the element.
2. Then we go to the corresponding father SiteDetails by using .. xpath selector.
3. Lastly we extract the value of SiteID from the needed SiteDetails element.

Good luck =)