PHP Object as XML Document

I'd agree with using PEAR's XML_Serializer, but if you want something simple that supports objects/arrays that have properties nested, you can use this.

class XMLSerializer {

    // functions adopted from http://www.sean-barton.co.uk/2009/03/turning-an-array-or-object-into-xml-using-php/

    public static function generateValidXmlFromObj(stdClass $obj, $node_block='nodes', $node_name='node') {
        $arr = get_object_vars($obj);
        return self::generateValidXmlFromArray($arr, $node_block, $node_name);
    }

    public static function generateValidXmlFromArray($array, $node_block='nodes', $node_name='node') {
        $xml = '<?xml version="1.0" encoding="UTF-8" ?>';

        $xml .= '<' . $node_block . '>';
        $xml .= self::generateXmlFromArray($array, $node_name);
        $xml .= '</' . $node_block . '>';

        return $xml;
    }

    private static function generateXmlFromArray($array, $node_name) {
        $xml = '';

        if (is_array($array) || is_object($array)) {
            foreach ($array as $key=>$value) {
                if (is_numeric($key)) {
                    $key = $node_name;
                }

                $xml .= '<' . $key . '>' . self::generateXmlFromArray($value, $node_name) . '</' . $key . '>';
            }
        } else {
            $xml = htmlspecialchars($array, ENT_QUOTES);
        }

        return $xml;
    }

}

not quite an answer to the original question, but the way i solved my problem with this was by declaring my object as:

$root = '<?xml version="1.0" encoding="UTF-8"?><Activities/>';
$object = new simpleXMLElement($root); 

as opposed to:

$object = new stdClass;

before i started adding any values!

take a look at PEAR's XML_Serializer package. I've used it with pretty good results. You can feed it arrays, objects etc and it will turn them into XML. It also has a bunch of options like picking the name of the root node etc.

Should do the trick