PHP getName() 関数

<?php
$xml=<<<XML
<?xml version="1.0" standalone="yes"?>
<cars>
  <car id="1">Volvo</car>
  <car id="2">BMW</car>
  <car id="3">Saab</car>
</cars>
XML;

$sxe=new SimpleXMLElement($xml);
echo $sxe->getName() . "<br>";
foreach ($sxe->children() as $child)
  {
  echo $child->getName() . "<br>";
  }
?>