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

Christopher Blanton
Christopher Blanton
19,337 Points

Getting a 1520 Compile error on my Teacher.cs file

I'm having trouble with this error because it says that I haven't specified the return type but when I do it says it's already specified earlier in the class. I've also checked the cases in the Courses and Course constructors and classes to make sure they match.

Course.cs
namespace Treehouse.CodeChallenges
{
    public class Course
    {
        public int Id { get; set; }
        public string Title { get; set; }
        public string Description { get; set; }
        public int Length { get; set; }
        public int TeacherId { get; set; }
        public Teacher Teacher { get; set; }
    }
}
Teacher.cs
using System.Collections.Generic;

namespace Treehouse.CodeChallenges
{
    public class Teacher
    {

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

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

        public Courses() 
        {
            Courses = new List<Course>();
        }
    }
}

1 Answer

The default constructor in Teacher.cs should be for Teacher and not for Courses, so instead of public Courses(), try public Teacher().