gistfile1.txt

    public class ObjectStore {

        private static Dictionary<int, SalesObject> _objects = new Dictionary<int, SalesObject>();

        public static T GetObject<T>(int contactId) where T : SalesObject {
            SalesObject tmpAccessory = null;
            _objects.TryGetValue(contactId, out tmpAccessory);

            return (T)tmpAccessory;
        }

        public static void Store(int contactId, SalesObject accessory) {

            if (GetObject<SalesObject>(contactId) != null) {
                _objects.Remove(contactId);
            }

            _objects.Add(contactId, accessory);
        }

        public static void Clear(int contactId) {
            _objects.Remove(contactId);
        }
    }