SAP DI API：如何使用多张发票添加付款？

Question

我试图通过多张发票添加应用程序付款来发布消息。我正在使用C＃开发我的添加应用程序。 发布后，sap会为每个发票或付款明细创建一个付款，但假设这些付款的发票属于我的附加应用中的一个付款。 这是我的代码。

    Payments _pay = (Payments)company.GetBusinessObject(BoObjectTypes.oIncomingPayments);
    Recordset _oRecordSet = (Recordset)company.GetBusinessObject(SAPbobsCOM.BoObjectTypes.BoRecordset);
    _oRecordSet.DoQuery("select NextNumber from NNM1 where Series = 98");
    int docnum = int.Parse(_oRecordSet.Fields.Item(0).Value.ToString());
    int errCode = 0;

    _pay.DocNum = docnum;
    _pay.DocDate = pay.DocDate;
    _pay.TaxDate = pay.TaxDate;
    _pay.DueDate = pay.DocDueDate;
    _pay.CashSum = pay.CashSum;
    _pay.CashAccount = pay.CashAcct;
    _pay.Invoices.SumApplied = pay.TotalPaid;
    _pay.Invoices.AppliedFC = pay.TotalPaid;
    _pay.Invoices.InvoiceType = BoRcptInvTypes.it_Invoice;

    foreach (var i in pay.Details)
    {                                       
       InvoiceHeader inv = new InvoiceHeader();
       inv = context.InvoiceHeaders.FirstOrDefault(x => x.Id == i.TransactionDocumentNo);
       _pay.Invoices.DocEntry = Convert.ToInt32(inv.DocumentNumber);

       errCode = _pay.Add();

       if (errCode != 0)
       {
          string _errMsg = "";
          company.GetLastError(out errCode, out _errMsg);
       }
    }