DbContext

DbContext.cs

protected override void OnModelCreating(ModelBuilder modelBuilder)
{
    modelBuilder
        .Entity<Shipment>()
        .Property(e => e.State)
        .HasConversion(
            s => s.ToString(),
            s => s switch {
              nameof(OrderPlacedState) => new OrderPlacedState(),
              nameof(InTransitState) => new InTransitState(),
              nameof(InCustomsState) => new InCustomsState(),
              nameof(CustomsClearedState) => new CustomsClearedState(),
              nameof(OutForDeliveryState) => new OutForDeliveryState(),
              nameof(DeliveredState) => new DeliveredState(),
              nameof(NotDeliveredState) => new NotDeliveredState(),
              _ => throw new ArgumentOutOfRangeException(s)
            }
        );
}