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C# Entity Framework Basics Extending Our Entity Data Model Defining a Many-to-Many Relationship

Frantyk Andrii
Frantyk Andrii
35,423 Points
Posted by Frantyk Andrii
Frantyk Andrii
35,423 Points

What is wrong with my code?

using System.Collections.Generic; 

namespace Treehouse.CodeChallenges
{
    public class Course
    {
        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 ICollection<Student> Students { get; set; } 
        public Course() 
        { 
            Students = new List<Student>; 
        }
        public Teacher Teacher { get; set; }
    }
}

Course.cs

using System.Collections.Generic; 

namespace Treehouse.CodeChallenges
{
    public class Course
    {
        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 ICollection<Student> Students { get; set; } 
        public Course() 
        { 
            Students = new List<Student>; 
        }
        public Teacher Teacher { get; set; }
    }
}

Student.cs

namespace Treehouse.CodeChallenges
{
    public class Student
    {
        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
    }
}

1 Answer

James Churchill
STAFF
James Churchill
Treehouse Teacher
James Churchill
James Churchill
Treehouse Teacher

Frantyk,

You're missing a set of parentheses when instantiating the Students collection.

Instead of:

Students = new List<Student>;

You need:

Students = new List<Student>();

Thanks ~James