Expression cannot be type-converted

mfh

I try to get the "Quantity" from the Sales Line in a dataport with Data Item "Purch. Rcpt. Line". The code is in the OnBeforeExportRecord:

IF gRecSalesLine.GET("Purch. Rcpt. Line"."Sales Order No.","Purch. Rcpt. Line"."Sales Order Line No.") THEN
  gDecBaseQty := gRecSalesLine.Quantity;

If I execute the dataport, I receive the error:
'The expression Code cannot be type-converted to a Option value'.

I don't understand this message. Why is it complaining about a Option value?

mfh

Oeps! Sorry to have bothered you guys. I found a topic in which Mark answers my question: I just added the "Sales Line"."Order Type"::Order to my query!