James Hartig

function toXML($object, $rootName="", $indexName="") {
    $xmlDoc = new DOMDocument();

    if (!is_string($object)) { //we gotta hope its an array
        if ($rootName) {
            $root = $xmlDoc->appendChild(
                    $xmlDoc->createElement($rootName));
        }
        $arrayParse = function($array, $root) use (&$arrayParse, &$xmlDoc, $indexName) {
            foreach ($array as $key => $val) {
                if (is_array($val)) {
                    if (is_numeric($key) && $indexName) {
                        $newRoot = $root->appendChild(
                                   $xmlDoc->createElement($indexName));
                    } else if (is_numeric($key)) {
                        $newRoot = $root->appendChild(
                                   $xmlDoc->createElement("Object"));
                    } else {
                        $newRoot = $root->appendChild(
                                   $xmlDoc->createElement($key));
                    }
                    $arrayParse($val, $newRoot);
                } else {
                    $root->appendChild(
                    $xmlDoc->createElement($key, $val));
                }
            }
        };
        if (isset($root)) {
            $arrayParse($object, $root);
        } else {
            $arrayParse($object, $xmlDoc);
        }
    } else {
        if ($rootName) {
            $root = $xmlDoc->appendChild(
                    $xmlDoc->createElement($rootName, $object));
        } else {
            $root = $xmlDoc->appendChild(
                    $xmlDoc->createElement("Object", $object));
        }
    }
    $xmlDoc->formatOutput = true;
    return $xmlDoc->saveXML();
}