I have two separate grids on my form, a parent grid and a child grid. The parent grid's data structure has an identity column and the child incorporates that field as part of its primary key. Both grid's datasources are pointed to bindingSources that point to ES collections.

When the parent record changes I load the corresponding child records. 

            //The parent record has changed. Load the new child details
            User usr = new User();
            usr = (User)userCollectionBindingSource.Current;
            userCustomerLocationsCollection1 = usr.UserCustomerLocationsCollectionByUserId;
            bindingSourceUserCustLocations.DataSource = userCustomerLocationsCollection1;

If I add a new parent record, its identity field is not set; when I move directly to the child record, how should I set the key field as the parent's value is not yet set. Is there a best method for doing this?

Hi

I'm assuming that if you're at the stage of adding a child record then you're happy with the parent record and therefore it could be saved so why not check the state of the parent record in your code to add/update children and if the parent is new/added, call save on the parent - then I assume your current problem is no longer an issue?

Just an idea

Cheers

Martin

I have to get this to work with the Infragistics grid so I am not sure how relevant this is but one question. Let's say I set the parent PK to -1 and the PK field in the child record also to -1. Then the save takes place the parent PK might be set to 100, will a save of the child records also automatically set their PK field to 100 or would it be left at -1 since it in not an identity field?

 I think the dataset lets you save parent and child records like this. It keeps a track of those disconnected values and then sets them to real values when the rows are added to the database.