public function ExportVoucherCodes()
    {
        $sReturn = '';

        if ($this->AllowExportingVoucherCodes()) {
            $oVouchers = TdbShopVoucherList::GetList("SELECT * FROM `shop_voucher` WHERE `shop_voucher_series_id`='".MySqlLegacySupport::getInstance()->real_escape_string($this->sId)."'");
            $oVouchers->GoToStart();
            $count = 0;
            while ($oVoucher = $oVouchers->Next()) {
                $aCsvVouchers[$count][0] = str_replace('"', '""', $oVoucher->fieldCode);
                if ('0000-00-00 00:00:00' != $oVoucher->fieldDatecreated) {
                    $aCsvVouchers[$count][1] = date('d.m.Y H:i', strtotime($oVoucher->fieldDatecreated));
                } else {
                    $aCsvVouchers[$count][3] = '';
                }
                $aCsvVouchers[$count][2] = $oVoucher->fieldIsUsedUp;
                if ('0000-00-00 00:00:00' != $oVoucher->fieldDateUsedUp) {
                    $aCsvVouchers[$count][3] = date('d.m.Y H:i', strtotime($oVoucher->fieldDateUsedUp));
                } else {
                    $aCsvVouchers[$count][3] = '';
                }
                ++$count;
            }

            $sCsv = '';
            for ($i = 0; $i < count($aCsvVouchers); ++$i) {
                $sCsv .= '"'.implode('";"', $aCsvVouchers[$i])."\"\n";
            }
            $sCsv = '"'.TGlobal::OutHTML(TGlobal::Translate('chameleon_system_shop.voucher.export_column_code')).'";"'.TGlobal::OutHTML(TGlobal::Translate('chameleon_system_shop.voucher.export_column_created')).'";"'.TGlobal::OutHTML(TGlobal::Translate('chameleon_system_shop.voucher.export_column_spent')).'";"'.TGlobal::OutHTML(TGlobal::Translate('chameleon_system_shop.voucher.export_column_spent_date'))."\"\n".$sCsv;

            while (@ob_end_clean()) {
            }
            header('Cache-Control: must-revalidate');
            header('Pragma: must-revalidate');
            header('Content-type: application/csv');
            header('Content-disposition: attachment; filename=ShopVouchers.csv');

            echo $sCsv;

            exit(0);
        } else {
            echo 'Keine Berechtigung';
        }
    }