private void UIAddGrade() { int studentId, homeworkId, week, noExemptions; double grade; string feedback; try { Console.Write("Enter the id of the student: "); studentId = Convert.ToInt32(Console.ReadLine()); Console.Write("Enter the id of the homework: "); homeworkId = Convert.ToInt32(Console.ReadLine()); Console.Write("Enter the week: "); week = Convert.ToInt32(Console.ReadLine()); Console.Write("Enter the number of exemptions: "); noExemptions = Convert.ToInt32(Console.ReadLine()); Student student = studentService.FindStudent(studentId); Homework homework = homeworkService.FindHomework(homeworkId); if (student != null && homework != null) { Console.WriteLine("The maximum grade is: " + gradeService.GetMaximumGradeForStudentOnHomeworkIntoWeek(student, homework, week, noExemptions)); Console.Write("Enter the grade: "); grade = Convert.ToDouble(Console.ReadLine()); Console.Write("Enter the feedback: "); feedback = Console.ReadLine(); Grade gradeObj = this.gradeService.AddGrade(new Grade(studentId, homeworkId, grade, week, feedback), noExemptions); if (gradeObj == null) { Console.Write("Successfully added the grade!"); } else { Console.Write("Failed to add the grade!"); } } else { Console.Write("The student or the homework doesn't exist!"); } } catch (Exception ex) { Console.Write(ex.Message); } }