?php 
$xml=XML
cars> 
car name="Volvo"> 
child/> 
child/> 
child/> 
child/> 
/car> 
car name="BMW"> 
child/> 
child/> 
/car> 
/cars> 
XML;
$elem=new SimpleXMLElement($xml); 
foreach ($elem as $car) 
{ 
printf("%s has %d children.br>", $car['name'], $car->count()); 
} 
?>

count();