C#: Bad design of class (first OOP)

Question

This is homework!!! Please do not interpret this as me asking for someone to code for me.

My Program: http://pastebin.com/SZP2dS8D

This is my first OOP. The program works just fine without user input(UI), but the implementation of it renders my design partially ineffective. I am not using a List collection because of assignment restrictions. My main goal is to have everything running from the Transcript class. Here are some issues I am running into:

• Allowing the user to add new course without having to create a new instance of Transcript
  each time
• Associating the Courses added to a specific Quarter

Here is some pseudo code to show what I am trying to accomplish. I have been experimenting with it, but have yet to succeed.

Please enter the quarter: (user input)
Would you like to add a course? 

while (true)

Enter Course/Credits/Grade

//new Course information populated with user input 
transcript.AddCourse.to specific Quarter((Fall 2013) new Course("Math 238", 5, 3.9));
transcript.AddCourse.to specific Quarter((Fall 2013) new Course("Phys 223", 5, 3.8));
transcript.AddCourse.to specific Quarter((Fall 2013) new Course("Chem 162", 5, 3.8));

MY QUESTION[S]: Should I keep the Transcript class, or discard it? With the current functionality of creating a new course, is it possible to keep it this way while using UI, or do I need to head back to the chalk board and reconfigure?

Hopefully this is coherent and not too broad. If clarification is needed please ask and I will me more than happy to provide more details.

Answer 1

I would consider the following compositon

public class Transcript
{
  public Quarter[] Quarters{get;set;}
}

public class Quarter
{
  public Course[] Courses{get;set;}
}

You only need one instance of the transcript class. This will enable you to model n quarters (multiple years) with n courses per quarter.

In your input loop you can add new courses/quarters in response to user input

Answer 2

There are a lot of ways to model this problem and I think you're right to have a transcript class, but instead of thinking that a quarter has a set of courses I would suggest that which quarter a course is offered is a property of the course. For example:

public class Transcript
{
    private List<Course> courses_ = new List<Course>();

    public IEnumerable<Course> Courses {get { return courses_; }

    public IEnumerable<Course> GetCoursesFor(int year, int quarter)
    {
        return courses_.Where(course => course.Year == year && course.Quarter == quarter);
    }

    public void AddCourse(Course course)
    {
        courses_.Add(course);
    }
}


public class Course
{
    public int Year {get; private set;}
    public int Quarter {get; private set;}
    // ... other members
}