public ActionResult Index()
 {
     _viewMessageLogic.SetViewMessageIfExist();
      var importModel = new ImportDataModel();
      ViewBag.GradeId = new SelectList(_gradeRepository.Query(x => x), "Id", "Name", 0);
      ViewBag.Year = new SelectList(_academicYearRepository.Filter(x => x.IsActive).Select(x => x.Year).Distinct().ToList());
      ViewBag.Section = new SelectList(new List<string> { "A", "B", "C" }, "A");
      return View(importModel);
 }
        public ActionResult Index(ImportDataModel importModel)
        {
            var validImageTypes = new []
            {
                "application/vnd.ms-excel"
            };
            bool errorExcel;
            if (importModel.UploadFile != null && importModel.UploadFile.ContentLength > 0)
                errorExcel = !validImageTypes.Contains(importModel.UploadFile.ContentType);
            else
                errorExcel = true;
            if(errorExcel)
                ModelState.AddModelError("UploadFile", "Por favor seleccione un archivo de Excel");
            var academicYear = _academicYearRepository.GetByFields(importModel.Year, importModel.GradeImport, importModel.Section);
            if (academicYear == null)
                ModelState.AddModelError("Year", "No existe ese año academico");
            ViewBag.GradeId = new SelectList(_gradeRepository.Query(x => x), "Id", "Name", 0);
            if (!ModelState.IsValid)
            {
                return View(importModel);
            }
            var myDataSet = _importDataRepository.GetDataSetFromExcelFile(importModel.UploadFile);
            try
            {
                _importDataRepository.Import(myDataSet, academicYear);
            }
            catch(Exception ex)
            {
                _viewMessageLogic.SetNewMessage("Error!", ex.Message, ViewMessageType.ErrorMessage);
                return RedirectToAction("Index");
            }

            const string title = "Importación de Datos Correcta";
            var content = string.Format("Se importaron datos para el año: {0}, grado: {1} y sección: {2}"
                                        , importModel.Year // 0
                                        , importModel.GradeImport // 1
                                        , importModel.Section // 2
                                       );
            _viewMessageLogic.SetNewMessage(title, content, ViewMessageType.InformationMessage);
            return RedirectToAction("Index");
        }