- var_dump: documentation ( source)
<?php
$string = 'D7007S';
$writer = new XMLWriter;
$writer->openMemory();
//$writer->startElement('example');
$writer->text($string);
//$writer->endElement();
$xml = $writer ->outputMemory();
var_dump($xml, $xml === '<example>D7007S</example>', $string);