如何使用php删除基于子属性的XML标记？

I have an XML like below

<entries>
  <entry>
    <title lang="en">Sample</title>
    <entrydate>0</entrydate>
    <contents>0</contents>
    <entrynum>0</entrynum>
  </entry>
  <entry>
    <title lang="fr">Sample</title>
    <entrydate>1</entrydate>
    <contents>1</contents>
    <entrynum>1</entrynum>
  </entry>
</entries>

Is there a way in PHP to delete the parent node (entry) based on the title lang attribute? I need to keep only the en ones, so in this case I would need to get the XML without the second entry node.

I tried looking around but couldn't find any solution...

You need to use DOMDocument class to parse string to XML document. Then use DOMXpath class to find target element in document and use DOMNode::removeChild() to remove selected element from document.

$doc = new DOMDocument(); 
$doc->loadXML($xml);
$xpath = new DOMXpath($doc);
// select target entry tag
$entry = $xpath->query("//entry[title[@lang='fr']]")->item(0);
// remove selected element
$entry->parentNode->removeChild($entry);
$xml = $doc->savexml();

You can check result in demo

You could also read your file and generated new one with your modification

<?php
$entries = array('title' => "What's For Dinner",
'link' => 'http://menu.example.com/',
'description' => 'Choose what to eat tonight.');
print "<entries>
";
foreach ($entries as $element => $content) {
print " <$element>";
print htmlentities($content);
print "</$element>
";
}
print "</entries>";
?>

Use the method described in this answer, i.e.

<?php
$xml = simplexml_load_file('1.xml');

$del_items = [];
foreach ($xml->entry as $e) {
  $attr = $e->title->attributes();
  if ($attr && $attr['lang'] != 'en') {
    $del_items []= $e;
  }
}

foreach ($del_items as $e) {
  $dom = dom_import_simplexml($e);
  $dom->parentNode->removeChild($dom);
}

echo $xml->asXML();

Output

<?xml version="1.0" encoding="UTF-8"?>
<entries>
  <entry>
    <title lang="en">Sample</title>
    <entrydate>0</entrydate>
    <contents>0</contents>
    <entrynum>0</entrynum>
  </entry>

</entries>

The items cannot be removed within the first loop, because otherwise we may break the iteration chain. Instead, we collect the entry objects into $del_items array, then remove them from XML in separate loop.