XML build through PHP

$items = array('name'=>'Tony','age'=>'27');
$docXML = '<?xml version="1.0" encoding="iso-8859-1"?><root>';
foreach ($items as $k => $v) {
     $docXML .= '<'.$k.'>'.$v.'</'.$k.'>';
}
$docXML .= '</root>';

// This is an important line, you need to send a header
header('Content-Type: text/xml');
echo $docXML;