php simple xml how to read multiple nodes with different child node levels

Question

I have an xml file that has different named nodes and multi level child nodes (that are different between each node.) How should I access the data? Will it require many nested for loops?

Here is a sample of the xml code:

       <start_info>
          <info tabindex="1">
                  <infonumber>1</infonumber>
                  <trees>green</trees>
           </info>
       </start_info>

          <people>
                <pe>
                    <people_ages>
                       <range number="1">
                          <age value="1">1</age>
                          <age value="2">2</age>
                        </range>
                    </people_ages>
                </pe>
          </people>

Here is my code so far:

$xml = simplexml_load_file("file.xml");

echo $xml->getName() . "start_info";

foreach($xml->children() as $child)
  {
  echo $child->getName() . ": " . $child . "<br />";
  }

Answer 1

Here is some example code that I hope can point you in the right direction. Essentially, it is walking the DOMDocument echoing the element name and values. Note that the whitespace between the elements is significant, so for the purposes of the demo, the XML is compacted. You may find a similar issue loading from a file, so if you are not getting the expected output you might need to strip whitespace nodes.

You could replace the //root/* with a different XPath for example //people if you only wanted the <people> elements.

<?php
    $xml = <<<XML
    <root><start_info><info tabindex="1"><infonumber>1</infonumber><trees>green</trees></info></start_info>
    <people><pe><people_ages><range number="1"><age value="1">1</age><age value="2">2</age></range></people_ages></pe></people>
    </root>
    XML;

    $dom = new DOMDocument();
    $dom->recover = true;
    $dom->loadXML($xml);
    $xpath = new DOMXPath($dom);
    $nodelist = $xpath->query('//root/*');
    foreach ($nodelist as $node) {
        echo "\n$node->tagName";
        getData($node);
    }

    function getData($node) {
        foreach ($node->childNodes as $child) {

            if ($child->nodeType == XML_ELEMENT_NODE) {
                echo ($child->tagName === '' ? '' : "\n").$child->tagName;
            }

            if ($child->nodeType == XML_TEXT_NODE) {
                echo '->'.$child->nodeValue;
            }

            if ($child->hasChildNodes()) {
                getData($child); // recursive call
            }
        }
    }
?>