使用XPath选择名称空间

Question

我一直在尝试在PHP中使用XPath从National Health Service API访问Atom提要.

数据如下所示:

<feed xmlns:s="http://syndication.nhschoices.nhs.uk/services" xmlns="http://www.w3.org/2005/Atom">
 <title type="text">NHS Choices - GP Practices Near Postcode - W1T4LB - Within 5km</title>
 <entry>
  <id>http://v1.syndication.nhschoices.nhs.uk/organisations/gppractices/27369</id>
  <title type="text">Fitzrovia Medical Centre</title>
  <updated>2011-08-20T22:47:39Z</updated>
  <link rel="self" title="Fitzrovia Medical Centre" href="http://v1.syndication.nhschoices.nhs.uk/organisations/gppractices/27369?apikey="/>
  <link rel="alternate" title="Fitzrovia Medical Centre" href="http://www.nhs.uk/ServiceDirectories/Pages/GP.aspx?pid=303A92EF-EC8D-496B-B9CD-E6D836D13BA2"/>
  <content type="application/xml">
   <s:organisationSummary>
    <s:name>Fitzrovia Medical Centre</s:name>
    <s:address>
     <s:addressLine>31 Fitzroy Square</s:addressLine>
     <s:addressLine>London</s:addressLine>
     <s:postcode>W1T6EU</s:postcode>
    </s:address>
    <s:contact type="General">
     <s:telephone>020 7387 5798</s:telephone>
    </s:contact>
    <s:geographicCoordinates>
     <s:northing>182000</s:northing>
     <s:easting>529000</s:easting>
     <s:longitude>-0.140267259415255</s:longitude>
     <s:latitude>51.5224357586293</s:latitude>
    </s:geographicCoordinates>
    <s:Distance>0.360555127546399</s:Distance>
   </s:organisationSummary>
  </content>
 </entry>
</feed>

我现在正在使用此代码来访问节点.

<?php   

$feedURL = 'http://v1.syndication.nhschoices.nhs.uk/organisations/pharmacies/postcode/W1T4LB.xml?apikey=&range=5';
$xml = file_get_contents($feedURL);
$sxml = new SimpleXMLElement($xml);
$sxml->registerXPathNamespace('a', 'http://www.w3.org/2005/Atom');
$sxml->registerXPathNamespace('s', 'http://syndication.nhschoices.nhs.uk/services');

$addr = $sxml->xpath('//s:address');

var_dump($addr[0]);

?>

这里$addr是空的但它应该有十个条目.

请有人解释打印出每个<s:addressLine>节点内容的好方法,并将邮政编码放入var中.

我在实践中使用名称空间原则,虽然这对我来说是相当新的.欣赏您可以传达的有关学习XPath和PHP SimpleXML模型的任何信息.

感谢帮助.

编辑 -

在看到下面给出的更新时,我决定将我的最终输出代码放入:

function doPharmacy($postcode, $request, $prev, $next)
{


    $feedURL = 'http://v1.syndication.nhschoices.nhs.uk/organisations/pharmacies/postcode/' . $postcode . '.xml?apikey=&range=5';
    $xml = file_get_contents($feedURL);
    $sxml = new SimpleXMLElement($xml);
    $sxml->registerXPathNamespace('a', 'http://www.w3.org/2005/Atom');
    $sxml->registerXPathNamespace('s', 'http://syndication.nhschoices.nhs.uk/services');

    ////////////// XPATH \\\\\\\\\\\\\\

    $addrLines = $sxml->xpath('/a:feed/a:entry[' . $request . ']/a:content/s:organisationSummary/s:address/s:addressLine');
    $nhsPostcode = $sxml->xpath('/a:feed/a:entry[' . $request . ']/a:content/s:organisationSummary/s:address/s:postcode');
    $tel = $sxml->xpath('/a:feed/a:entry[' . $request . ']/a:content/s:organisationSummary/s:contact/s:telephone');
    $distance = $sxml->xpath('/a:feed/a:entry[' . $request . ']/a:content/s:organisationSummary/s:Distance');
    $title = $sxml->xpath('/a:feed/a:entry[' . $request . ']/a:title');
    $link = $sxml->xpath('/a:feed/a:entry[' . $request . ']/a:link[@rel="alternate"]/@href');

    $nhsPostcode = array_pop($nhsPostcode); // always taking first node from set
    $tel = array_pop($tel);
    $distance = (double)array_pop($distance);
    $title = array_pop($title);
    $link = array_pop($link);


    ////////////// OUTPUT: JSON \\\\\\\\\\\\\\

    print '{"addr": "';

    foreach ($addrLines as $addr)
    {
        print $addr . '<br />'; // ok to use HTML tags in JSON
    }

    print '",';

    print '"postcode": "' . $nhsPostcode . '",';

    print '"tel": "' . $tel . '",';

    $num = number_format($distance, 2);

    print '"distance": "' . $num . '",';

    print '"title": "' . $title . '",';

    print '"link": "' . $link . '",';

    $nhsPostcode = urlencode($nhsPostcode);

    print'"mapsURL": "http://maps.googleapis.com/maps/api/staticmap?center=' . $nhsPostcode . '&zoom=15&size=155x137&sensor=false&scale=2",';

    print '"prev": "' . $prev . '",';

    print '"next": "' . $next . '"';

    print '}';
}

?>

Answer 1

这对我有用:

$addr = $sxml->xpath('//s:address');
foreach ($addr as $a) {
    $addressLine = $a->xpath('s:addressLine');
    foreach ($addressLine as $al) {
        echo (string)$al."<br/>";
    }
    $postalCode = $a->xpath('s:postcode');
    foreach ($postalCode as $p) {
        echo (string)$p."<br/>";
    }
}

哪个显示:

31 Fitzroy Square
London
W1T6EU