.Net DataGridView "Index 0 does not have a value."

Question

I am having trouble with a DataGridView. I have a collection of 3 Items bound to the grid, when trying to delete one of the items and reload the grid.

If have code of

If (dlg.ShowDialog() = DialogResult.OK) Then
     'Show dialog with grid on it
End If

On the opened dialog, I delete an item from the grid (which should in turn, delete the item from the collection, and re-load the grid), and it returns to the "If (dlg.show..." line, with the error of

"A first chance exception of type 'System.IndexOutOfRangeException' occurred in System.Windows.Forms.dll

Additional information: Index 2 does not have a value. "

(I have break into debugger set on for common language runtime errors)

I can understand this error if i were trying to access any cells, row or columns, but im not, and then I would expect the exception to stop on the line of code that is trying to access this grid data, not the "If (dlg.ShowDialog()... " line

Any ideas? Cheers

Answer 1

It is possible that since you are showing a modal dialog, the error that is thrown is shown there. Have you tried to set a break point in the line of code that actually does the deleting from the grid/collection to see if the error is coming from that?

Answer 2

I have discovered that if you add in

DataGridView.DataSource = Nothing
DataGridView.Refresh()

before resetting the grid to the collection (with the deleted item removed)

DataGridView.DataSource = MyCollection

It works like a charm. Still interested as to why you have to do this.