I am putting together an editor for an application I am creating.

The data ultimately resides on a SQL server.

The application loads some of the data from the server into a dataset, which is used by a bindingsource which is then used by a bindingnavigator. (wow that's a mouthful).

The issue is, the dataset contains some constraints, one of them involves a "code" that must be unique, similar to an account number for any company, they can't repeat but are more useful to end users than the identity data.

Anyway, if I have 2 records, and the code for one record is A and is B for the other...if I change B to A, I get a constraint exception. Great! That's what's supposed to happen, except that there are other text box controls on the form that are bound too dataset fields that have a unique constraint...is there any way at all of finding out what form control contains the invalid data?

Also, to throw another wrench in the gears, the form contains 2 total bindingsources, both of which are bound to tables that have unique constraints.

I have looked everywhere I can think of and I can't find anything on handling these errors correctly other than a message box that just shows the standard e.Message error (which is useless if you ask me).


Have you looked at the inner exception? Not sure if this will help, but it's the first place I'd look.

Have you looked at the inner exception? Not sure if this will help, but it's the first place I'd look.

Me too...it's null :(

The exception occurs when EndEdit() is called on the bindingSource with the error. I just can't figure this out...The exception message says: "Column 'ParentCode' is constrained to be unique. Value 'ATI2' is already present." so the information I am looking for can be found, it has to be there...I just can't find it!

Here's the exception details from the debugger, do you see anything that I might be missing?

System.Data.ConstraintException was caught
Message=Column 'ParentCode' is constrained to be unique. Value 'ATI2' is already present.
at System.Data.UniqueConstraint.CheckConstraint(DataRow row, DataRowAction action)
at System.Data.DataTable.RaiseRowChanging(DataRowChangeEventArgs args, DataRow eRow, DataRowAction eAction, Boolean fireEvent)
at System.Data.DataTable.SetNewRecordWorker(DataRow row, Int32 proposedRecord, DataRowAction action, Boolean isInMerge, Boolean suppressEnsurePropertyChanged, Int32 position, Boolean fireEvent, Exception& deferredException)
at System.Data.DataRow.EndEdit()
at System.Data.DataRowView.EndEdit()
at System.Windows.Forms.CurrencyManager.EndCurrentEdit()
at System.Windows.Forms.BindingSource.EndEdit()
at DATA.Editors.Companies.toolStripButton1_Click(Object sender, EventArgs e) in U:\Projects\DATA\DATA\Editors\Companies.cs:line 38