RE: How to do partial packing slip by x++ code

I tried from different scenario, but it didn't work out. any solution pls update. it would be a very helpful for me.

Other scenario which i applied :

SalesTable          salesTable;

  SalesFormLetter     salesInvoice;

   Query               query;

   QueryRun            queryRun;

   QueryBuildDataSource qbds;

   ;

   salesTable        =     SalesTable::find('SO_00002727');

  query   =   new Query(QueryStr(SalesUpdatePackingSlip));

  qbds = query.dataSourceTable(tableNum(SalesLine));

    qbds.addRange(fieldNum(SalesLine, SalesId)).value(queryValue('SO_00002727'));

 qbds.addRange(fieldNum(SalesLine, ItemId)).value(queryValue('item1'));

       queryRun = new QueryRun(query);

       salesInvoice = SalesFormLetter::construct(DocumentStatus::PackingSlip);

       salesInvoice.chooseLinesQuery(queryRun);

       salesInvoice.update(salesTable);

Any solution for this. Pls update????

Thanks in advance