To get the number sequence based on the date selection financial year.

 For that requirement in project parameters fom created new field

added field in numbersequencereference  tables and make relation with numbersequence table for that table

Code:

    TransDate               fiscalStartdate;
    FiscalCalendarPeriod    fiscalCalendarPeriod;
    RecId                   calendarRecId;
    RefRecId                oldNumberSeq;
    NumberSequenceTable     numberSequenceTable;
    numberSeqFormHandler    numberSeqFormHandler;

calendarRecId = Ledger::fiscalCalendar(CompanyInfo::current());

    fiscalCalendarPeriod = FiscalCalendars::findPeriodByPeriodCodeDate(calendarRecId, today(),                                                FiscalPeriodType::Operating);

    fiscalStartdate = fiscalCalendarPeriod.StartDate;

    if (ProjectOnAccount_TransDate.dateValue() <= fiscalStartDate )

    {

    numberSeqFormHandler = numberSeqFormHandler::newForm(projparameters::numRefProjTransIdBase().NumberSequenceId,element,ProjOnAccTrans_DS,fieldNum(ProjOnAccTrans,TransId));

        numberSeqFormHandler.formMethodDataSourceCreate();

    }

    else if (ProjectOnAccount_TransDate.dateValue() >= fiscalStartDate )

    {

        numberSeqFormHandler = numberSeqFormHandler::newForm(projparameters::numRefProjTransIdBase().NewNumberSequenceId,element,ProjOnAccTrans_DS,fieldNum(ProjOnAccTrans,TransId));

        numberSeqFormHandler.formMethodDataSourceCreate();

    }