public ParkType(ParkService parkService) { _parkService = parkService; Name = "Park"; Field(d => d.Id).Description("The id of the park."); Field(d => d.Name).Description("The name of the park."); Field(d => d.Location, true); Field(d => d.OpeningHours, true); Field(d => d.ClosingHours, true); Field(d => d.Logo, true); Field <ListGraphType <RideType>, List <Ride> >() .Name("rides").ResolveAsync(ctx => _parkService.GetRidesByParkId(ctx.Source.Id)); }