private static function encodeValueXml($value)
    {
        if ($value instanceof \DateTime) {
            return $value->format('Y-m-d\TH:i:s.000\Z');
        }
        else if (is_bool($value)){
            return $value ? 'true' : 'false';
        } else {
            return $value;
        }
    }
private static function encodeValueXml($value)
    {
        if ($value instanceof \DateTime) {
            return $value->format('Y-m-d\TH:i:s.000\Z');
        }
        else if (is_bool($value)){
            return $value ? 'true' : 'false';
        } else {
            return $value;
        }
    }
private static function encodeValueXml ( $ value ) { if ( $ value instanceof \ DateTime ) { return $ value -> format ( 'Y-m-d\TH:i:s.000\Z' ) ; } else if ( is_bool ( $ value ) ) { return $ value ? 'true' : 'false' ; } else { return $ value ; } }
Helper function to convert a value into XML

@param mixed $value The value of the property.

@returns string The XML.
Helper function to convert a value into XML