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

In Course.cs define a many-to-many relationship between courses and students by adding the following to the Course class

I am confused, I understood the video to explain that was what was needed. But the compiler complains: error CS1520: Class, struct, or interface method must have a return type" Where am I going wrong here?

Course.cs
// A using directive for the System.Collections.Generic namespace
using System.Collections.Generic;
namespace Treehouse.CodeChallenges
{
    public class Course
    {
        //  Compiler complains: error CS1520: Class, struct, or interface method must have a return type
        public Students()
            // A default constructor that initializes the Students property to an instance of List<Student> 
        {
            Students = new List<Student>();
            }
        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; }
        // A navigation collection property named Students of type ICollection<Student>
        public ICollection<Students> Students { 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

Steven Parker
Steven Parker
231,198 Points

A constructor must have the same name as the class itself.

In this case, the name of the class is "Course", but you named your constructor "Students" instead.

Also, when you created your Students property, instead of giving it the type "ICollection<Student>" (singular), you wrote "ICollection<Students>" (plural) instead.