GDS\Gateway\ProtoBuf::beginTransaction PHP Method

    public function beginTransaction($bol_cross_group = FALSE)
    {
        $obj_request = new BeginTransactionRequest();
        if ($bol_cross_group) {
            $obj_request->setCrossGroup(TRUE);
        }
        $obj_response = $this->execute('BeginTransaction', $obj_request, new BeginTransactionResponse());
        return isset($obj_response->transaction) ? $obj_response->transaction : null;
    }