Datagrid binding to collectionbase implementation

[JontyMC]

I've created a collection of objects that implement a certain interface. I've then bound a datagrid to this collection, but when I try to edit the collection via the datagrid I get the following exception:

System.ArgumentOutOfRangeException: Specified argument was out of the range of valid values.
Parameter name: Index was out of range.  Must be non-negative and less than the size of the collection.
   at System.Collections.CollectionBase.System.Collections.IList.get_Item(Int32 index)
   at System.Windows.Forms.CurrencyManager.CancelCurrentEdit()
   at System.Windows.Forms.DataGrid.HandleEndCurrentEdit()
   at System.Windows.Forms.DataGrid.OnLeave_Grid()
   at System.Windows.Forms.DataGrid.OnLeave(EventArgs e)
   at System.Windows.Forms.Control.NotifyLeave()
   at System.Windows.Forms.ContainerControl.UpdateFocusedControl()

Any ideas why?

Jon

"There are 10 types of people in the world... those who understand binary and those who don't.

 

[NeilTrain]

If nothing is selected in the datagrid, "I THINK" the SelectedIndex property is -1, which of course can not be the index of a collection, which must be zero or positive.

you will have to check to ignore accessing the collection when the selected index is negative or null.

Ive never tied a collection to a Datagrid but I had the exact same problem when tying it to a listbox. I'm assuming this is the same cause though.

 

[JontyMC]

Something is selected, but I solved the problem. I was using DataSource property at run-time, when I switched to SetDataBinding it was fine.

Thanks

Jon

"There are 10 types of people in the world... those who understand binary and those who don't.