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

I don't understand why I have a compiler error.

I have a compiler error stating something about needing a "call" and I don't understand why. What is my code lacking?

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

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

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

        public ICollection<Course> Courses { get; set; }
    }
}

3 Answers

Ben Reynolds
Ben Reynolds
35,170 Points

You named your Teacher constructor "Courses", rename it to Teacher to match the class name and it should pass.

Steven Parker
Steven Parker
231,198 Points

I'm not sure what error you were seeing. The one I got was: "error CS1520: Class, struct, or interface method must have a return type".

But the actual issue is the constructor name. Constructors must have the same name as the class itself, but here in the "Teacher" class the constructor is named "Courses". Just change that to "Teacher" and you should pass the challenge.

Steven Parker
Steven Parker
231,198 Points

And I have to do a better job of remembering to refresh an old window before composing an answer! :wink:

Thanks, guys! That was the problem! I appreciate your help!