While making API you can have a different kind of response and you have to handle that for displaying data

public IHttpActionResult GetDetails(string Id)
        {
            logger.Info("GetDetailsById method called");

           // BadRequest detected

            if (string.IsNullOrEmpty(Id))
            {
                logger.Error("Id is empty");
                return BadRequest("Id is empty!");
            }

            try
            {
                var existing = DetailsDataOperations.GetPublicDetailsById(Id);

           // URL not found detected

                if (existing == null)
                    return NotFound();

           // Everything goes fine then OK

                logger.Info("GetDetailsById method completed");
                return Ok(existingDetail);
            }

           // Internal server error gets detected
            catch (Exception ex)
            {
                logger.Error(string.Format("Id : {0}",Id), ex);
                return InternalServerError(ex);
            }
        }

We use IHttpActionResult  class which contains definition of these return types