function _process_submission($method) {
        $submission = array();
        if (!empty($this->_ajaxformdata)) {
            $submission = $this->_ajaxformdata;
        } else if ($method == 'post') {
            if (!empty($_POST)) {
                $submission = $_POST;
            }
        } else {
            $submission = $_GET;
            merge_query_params($submission, $_POST); // Emulate handling of parameters in xxxx_param().
        }

        // following trick is needed to enable proper sesskey checks when using GET forms
        // the _qf__.$this->_formname serves as a marker that form was actually submitted
        if (array_key_exists('_qf__'.$this->_formname, $submission) and $submission['_qf__'.$this->_formname] == 1) {
            if (!confirm_sesskey()) {
                print_error('invalidsesskey');
            }
            $files = $_FILES;
        } else {
            $submission = array();
            $files = array();
        }
        $this->detectMissingSetType();

        $this->_form->updateSubmission($submission, $files);
    }