private static void SortStudents(string sortOrder, List <StudentEvaluationViewModel> invitationToStudy, StudentEvaluationListViewModel model)
        {
            var sort = new Dictionary <string, List <StudentEvaluationViewModel> >
            {
                { "PercentageGrade", invitationToStudy.OrderByDescending(s => s.PercentageGrade).ToList() },
                { "ConversationGrade", invitationToStudy.OrderByDescending(s => s.ConversationGrade).ToList() },
                { "FinalAverageGrade", invitationToStudy.OrderByDescending(s => s.FinalAverageGrade).ToList() },
                { "Priority", invitationToStudy.OrderByDescending(s => s.Priority).ToList() }
            };

            if (sortOrder != null)
            {
                if (sort.ContainsKey(sortOrder))
                {
                    model.StudentEvaluations = sort[sortOrder];
                }
            }
        }
        private static void AddSelectedCityToModel(string cityId, List <SelectListItem> stringCities, StudentEvaluationListViewModel model)
        {
            model.Cities = stringCities;
            var selectedCity = stringCities.FirstOrDefault(x => x.Text == cityId);

            model.SelectedCity = selectedCity?.Text;
        }
        private static void AddSelectedAcceptancePeriodToModel(string examId, List <SelectListItem> stringAcceptancePeriods, StudentEvaluationListViewModel model)
        {
            model.AcceptancePeriods = stringAcceptancePeriods;
            var selectedAcceptancePeriods = stringAcceptancePeriods.FirstOrDefault(x => x.Text == examId);

            model.SelectedAcceptancePeriod = selectedAcceptancePeriods?.Text;
        }
        private static void AddSelectedCourseToModel(string courseId, List <SelectListItem> stringCourses, StudentEvaluationListViewModel model)
        {
            model.Courses = stringCourses;
            var selectedCourse = stringCourses.FirstOrDefault(x => x.Text == courseId);

            model.SelectedPriority = selectedCourse?.Text;
        }