TYPO3: Parse Flexform XML in Backend

<?php
use TYPO3\CMS\Core\Utility\GeneralUtility;
use TYPO3\CMS\Extbase\Service\FlexFormService;
 
$ffs = GeneralUtility::makeInstance(FlexFormService::class);
$flex = $ffs->convertFlexFormContentToArray($fieldArray['pi_flexform']);
?>