public bool WriteAll(IEnumerable <Person> people) { StringBuilder sb = new StringBuilder(); foreach (var item in people) { item.Id = -1; item.FavColour = UtilColor.Colors.FirstOrDefault(f => f.Id == item.FavColourId); //just to keep things in sync with Entity, Dumb hack sb.Append(UtilPerson.FromPerson(item)); } File.AppendAllText(CSVFilePath, sb.ToString()); _cachePeople.Clear(); return(true); }