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C# Entity Framework Basics Extending Our Entity Data Model Defining a Many-to-Many Relationship with an Explicit Bridge Entity

Defining a Many to-Many Relationship with an Explicit Bridge Entity Task 3 of 3

Need help finding my error

Course.cs
using System.Collections.Generic;

namespace Treehouse.CodeChallenges
{
    public class Course
    {
        public Course()
        {
            Students = new List<CourseStudent>();
        }

        public int Id { get; set; }
        public int TeacherId { get; set; }
        public string Title { get; set; }
        public string Description { get; set; }
        public int Length { get; set; }

        public Teacher Teacher { get; set; }
        public ICollection<CourseStudent> Students { get; set; }
    }
}
CourseStudent.cs
using System.Collections.Generic;

namespace Treehouse.CodeChallenges
{
    public class CourseStudent
    {
        public int Id { get; set; }
        public int CourseId { get; set; }
        public int StudentId { get; set; }
        public decimal Grade { get; set; }

        public Course Course { get; set; }
        public Student Student { get; set; }
    }
}
Student.cs
using System.Collections.Generic;

namespace Treehouse.CodeChallenges
{
    public class Student
    {
        public Student()
        {
             CourseStudent Students = new List<CourseStudent>();
        }

        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }

        public ICollection<Student> Students { get; set; }
    }
}

2 Answers

Steven Parker
Steven Parker
231,198 Points

Task 3 is much like task 2.

Remember in task 2 you had to change both the collection type and the initialization? For task 3 you do essentially the same thing in a different file.

But it doesn't look like you've changed the collection type yet.

Figured it out. Thank you Steven!