public ActionResult Index()
 {
     List<SelectListItem> citiesNames = PIWebAPIWrapper.GetCitiesName();
     List<SelectListItem> attributesNames = PIWebAPIWrapper.GetAttributesName();
     MainModel mainModel = new MainModel(citiesNames, attributesNames);
     return View(mainModel);
 }
        public ActionResult Index(MainModel mainModel)
        {
            mainModel.CitiesNames = PIWebAPIWrapper.GetCitiesName();
            mainModel.AttributesNames = PIWebAPIWrapper.GetAttributesName();

            int statusCode = PIWebAPIWrapper.SendValue(mainModel.SelectedCity, mainModel.SelectedAttribute, mainModel.Value);
            if (statusCode == 202)
            {
                mainModel.StatusMessage = "Success!";
            }
            else
            {
                mainModel.StatusMessage = "Error";
            }
            return View("Index", mainModel);
        }