Copy field from purchparmline to vendpackingslipjour and vendpackingsliptrans

I am added two customized fields in purchparmline.one field shold update to the vendpackingslipjour , another field should update vendpackingsliptrans.could u plz give me suggestions.

\Classes\PurchPackingSlipJournalCreate\initJournalLine

Look at this white paper to understand the form letter framework. technet.microsoft.com/…/hh272871.aspx

thank u sir .

\Classes\PurchPackingSlipJournalCreate\initJournalLine

purchparmline = _parmline as purchparmline ;

vendpackingsliptrans.amount = purchparmline .amount ;

\Classes\PurchPackingSlipJournalCreate\initHeader

select sum(amount) from purchparmline

where purchparmline .parmid == purchparmtable.parmid

&& purchparmline .tablerefid == purchparmtable.tablerefid ;

vendpackingslipjour .amount = purchparmline .amount;