SimpleXML - Remove xpath node

Question

I'm a little confused as to how I can delete a parent node of something which I can find via an xpath search:

$xml = simplexml_load_file($filename);
$data = $xml->xpath('//items/info[item_id="' . $item_id . '"]');
$parent = $data[0]->xpath("parent::*");
unset($parent);

So, it finds the item id, no problems there - but the unset isn't getting rid of this <items> node. All I want to do is remove the <items>...</items> for this product. Obviously, there are loads of <items> nodes in the xml file so it can't do unset($xml->data->items) as that would delete everything.

Any ideas much appreciated :-)

Answer 1

<?php
$xml = new SimpleXMLElement('<a><b/></a>');
unset($xml->b);
echo $xml->asxml();

this works as intended (removing the <b/> element fromt he document) because the __unset() method (or the equivalent in the modules code) is called.
But when you call unset($parent); it only removes the object reference stored in $parent, but it doesn't affect the object itself or the document stored in $xml. I'd revert to DOMDocument for this.

<?php
$doc = new DOMDOcument;
$doc->loadxml('<foo>
  <items>
    <info>
      <item_id>123</item_id>
    </info>
  </items>
  <items>
    <info>
      <item_id>456</item_id>
    </info>
  </items>
  <items>
    <info>
      <item_id>789</item_id>
    </info>
  </items>
</foo>');
$item_id = 456;

$xpath = new DOMXpath($doc);
foreach($xpath->query('//items[info/item_id="' . $item_id . '"]') as $node) {
  $node->parentNode->removeChild($node);
}
echo $doc->savexml();

prints

<?xml version="1.0"?>
<foo>
  <items>
    <info>
      <item_id>123</item_id>
    </info>
  </items>

  <items>
    <info>
      <item_id>789</item_id>
    </info>
  </items>
</foo>