Prepending data to XML file

Following from this: Appending data to XML file

I would instead like to prepend my new <thumbnail> element

I have this:

$xmldoc = new DOMDocument();
$xmldoc->load('sample.xml');



$thumbnail = $xmldoc->createElement('thumbnail');
$thumbnail->setAttribute('preview', 'This is a preview');
$thumbnail->setAttribute('previewURL', 'This is a URL');
$thumbnail->setAttribute('thumb', 'This is a Thumb');

$title = $xmldoc->createElement('title');
$title->appendChild($xmldoc->createCDATASection('This is Title'));
$thumbnail->appendChild($title);


$description = $xmldoc->createElement('description');
$description->appendChild($xmldoc->createCDATASection('This is Description'));
$thumbnail->appendChild($description);


$xmldoc->getElementsByTagName('thumbnails')->item(0)->appendChild($thumbnail);
$xmldoc->save('sample.xml');

Which is working just fine, but it is appending the <thumbnail> to the bottom before </thumbnails> </mainXML>

I would now instead like it to prepend it after the <thumbnails> open.

The current XML is here: ht开发者_开发问答tp://pastebin.com/4pWnFVfq

As you can see it appends in the bottom like i described.

How can i do this?

---

The following should do what you're looking for.

<?php

$xmldoc = new DOMDocument();
$xmldoc->load('sample.xml');



$thumbnail = $xmldoc->createElement('thumbnail');
$thumbnail->setAttribute('preview', 'This is a preview');
$thumbnail->setAttribute('previewURL', 'This is a URL');
$thumbnail->setAttribute('thumb', 'This is a Thumb');

$title = $xmldoc->createElement('title');
$title->appendChild($xmldoc->createCDATASection('This is Title'));
$thumbnail->appendChild($title);


$description = $xmldoc->createElement('description');
$description->appendChild($xmldoc->createCDATASection('This is Description'));
$thumbnail->appendChild($description);
$thumbs = $xmldoc->getElementsByTagName('thumbnails')->item(0);
$first_thumb = $thumbs->getElementsByTagName('thumbnail')->item(0);

$thumbs->insertbefore($thumbnail, $first_thumb);

$xmldoc->save('sample.xml');
?>