public IActionResult Add(Models.Student student) { if (student == null) { return(NotFound("student is null")); } var allStudentEmail = _diaryDbContext.Students.FirstOrDefault(user => user.Email == student.Email); var allStudentPhone = _diaryDbContext.Students.FirstOrDefault(user => user.Phone == student.Phone); if (allStudentEmail == null && allStudentPhone == null && !string.IsNullOrWhiteSpace(student.FirstName) && !string.IsNullOrWhiteSpace(student.LastName) && !string.IsNullOrWhiteSpace(student.Age.ToString()) ) { var group = _diaryDbContext.Groups.FirstOrDefault(x => x.Id == student.Group.Id); _diaryDbContext.Students.Add(new Models.Student { FirstName = student.FirstName, LastName = student.LastName, Age = student.Age, Email = student.Email, Phone = student.Phone, Password = CreateRandom.Password(), Group = group }); _diaryDbContext.SaveChanges(); return(RedirectToAction("Students", "Student")); } return(NotFound("Error Data")); }