php array转json、xml

class Encode{
public static function jsonEncode($code,$message,$data){
$result = array(
'code' => $code,
'message' => $message,
'data' => $data
);
return json_encode($result);
}

public static function xmlEncode($code,$message,$data){
$result = array(
'code' => $code,
'message' => $message,
'data' => $data
);
header("content-type:text/xml");
$xml = "<?xml version='1.0' encoding='utf-8'?>";
$xml .='<root>';
$xml .= self::toXml($result);
$xml .='</root>';
return $xml;
}
public static function toXml($result){
$xml = '';
foreach ($result as $key => $value) {
$xml .= "<{$key}>";
$xml .= is_array($value)?self::toXml($value):$value;
$xml .= "</{$key}>";
}
return $xml;
}