1-) C# DEVEXPRESS RMOS - How to show a group row count in a grid yazma

 gridViewAracBilgileri.GroupSummary.Add(DevExpress.Data.SummaryItemType.Count, string.Empty);

EKRAN GÖRÜNTÜSÜ

kaynak : https://supportcenter.devexpress.com/ticket/details/q446051/how-to-show-a-group-row-count-in-a-grid