PHP按属性删除XML节点

Question

Have tried numerous examples on SO but none have worked.

Goal: Remove a node (unit) and it's children, by specific id=

filename.xml

<archive>
  <unit id="0424670018">
    <data>Blah blah blah #1</data>
    <gdate>2018-05-28 00:42:46</gdate>
</unit>
  <unit id="0450170018">
    <data>Blah blah blah #2</data>
    <gdate>2018-05-28 00:45:01</gdate>
  </unit>
</archive>

Code used, not sure why it does not work when loaded:

$id = '0450170018';
$file = 'filename.xml';
$xml = simplexml_load_string($file);

foreach($xml->archive as $fileload){
    if($fileload->unit['@id'] == $id){
        $dom = dom_import_simplexml($fileload);
        $dom->parentNode->removeChild($dom);
    }
}

Answer 1

You can fetch the node using Xpath. It allows to fetch the matching node(s) directly.

$id = '0450170018';

$document = new DOMDocument();
$document->load('filename.xml');
$xpath = new DOMXpath($document);
foreach ($xpath->evaluate("//unit[@id='$id']") as $unitNode) {
  $unitNode->parentNode->removeChild($unitNode);
}
$document->save('filename.xml');