I know that WPF datagrid has \"RowEditEnding\" event , but I need to fire the event on after the Row has comitted to check if the newly added row is duplicated and merge the
You can use UpdateSourceTrigger=PropertyChanged on the binding of the property member for the datagrid. This will ensure that when CellEditEnding is fired the update has already been reflected in the observable collection.
see this post https://stackoverflow.com/a/27239243/9285072