Dear sir, I'm evaluating ES2008 and found a strange behaviour with databinding.

Suppose I have 2 tables

Order: OrderID, OrderDate

OrderDetail: OrderID, Product

Order.OrderID <->> OrderDetail.OrderID relationship

OrderID is not an AutoNumber/Identity so I must supply it in code.

Code1: This works perfectly 

dim o as new Order()
o.OrderID = 1
o.OrderDate = #01/01/2008#

dim od as OrderDetail()
od = o.OrderDetailCollectionByOrderID.AddNew()
od.Product = "XYZ"

o.Save()

Code2: This code does not work 

dim o_coll as new OrderCollection
dim o as Order()
dim od as OrderDetail()
dim bs as new bindingsource

bs.datasource=o_coll
o = bs.AddNew()
o.OrderID = 1
o.OrderDate = #01/01/2008#
bs.ResetBindings(false)
od = ctype(bs.current, OrderDetail).OrderDetailCollectionByOrderID.AddNew()
od.Product = "XYZ"

o_coll.Save()

In Code2, the field value of od.OrderID is nothing so I receive error when trying to save. I don't know why it is not automatically filled with o.OrderID value. Do I missing something here?

Regards,

Lewi 

Call AddNew() on the collection. With option strict and explicit on, this line will not compile for me, since bs.Current is an Order, not a OrderDetail.

od = ctype(bs.current, OrderDetail).OrderDetailCollectionByOrderID.AddNew()

If you are doing everything in code, you do not need to use a BindingSource.

dim o_coll as new OrderCollection

dim o as new Order()
o = o_coll.AddNew()
o.OrderID = 1
o.OrderDate = #01/01/2008#

dim od as OrderDetail()
od = o.OrderDetailCollectionByOrderID.AddNew()
od.Product = "XYZ"

o_coll.Save()