public ActionResult GetRealEstate([FromQuery] string NatbuildNo, [FromQuery] string RoomId) { MappingService mapping = new MappingService(); var mappingObj = mapping.GetOne(NatbuildNo, RoomId); if (mappingObj.RealEstateNo == null) { return(Ok(new BuildingResources())); } QueryParameter queryParameter = new QueryParameter() { EstateNo = mappingObj.RealEstateNo }; var building = BuildingService.GetOneRealEstate(queryParameter); if (building == null) { return(NotFound()); } else { return(Ok(building)); } }