EF Code First - Many To Many - c#-4.0

Question

I have a problem with devising a many to many relationship in code first. EF is creating the Junction table and associating the Fk's as I would expect, however when i try to access the User's MailingList collection, there are no entries.
I've implemented test data on Initialise via Seeding, the data is al present in the database.
I think the problem lies with the constructors for Users and MailingLists, but I'm uncertain. I want to be able to navigate the navigational property of User.MailingLists.
var user = db.Users.Find(1);
Console.WriteLine("{0}", user.EmailAddress); //This is Fine
Console.WriteLine("{0}", user.Address.PostCode); /This is Fine
foreach (MailingList ml in user.MailingLists) // this is 0
{
Console.WriteLine("{0}", ml.Name);
}
My model is below:-
public class User : IEntityBase
{
public User()
{
MailingLists = new List<MailingList>();
}
public int Id { get; set; }
public string Forename { get; set; }
public string Surname { get; set; }
public string EmailAddress { get; set; }
public DateTime? DateLastUpdated { get; set; }
public DateTime DateCreated { get; set; }
public bool IsDeleted { get; set; }
public virtual Address Address { get; set; }
public ICollection<MailingList> MailingLists { get; set; }
}
public class MailingList : IEntityBase
{
public MailingList()
{
Users = new List<User>();
}
public int Id { get; set; }
public string Name { get; set; }
public DateTime? DateLastUpdated { get; set; }
public DateTime DateCreated { get; set; }
public bool IsDeleted { get; set; }
public ICollection<User> Users { get; set; }
}
public class Address : IEntityBase
{
public int Id { get; set; }
public string AddressLine1 { get; set; }
public string AddressLine2 { get; set; }
public string AddressLine3 { get; set; }
public string City { get; set; }
public string County { get; set; }
public string PostCode { get; set; }
public DateTime? DateLastUpdated { get; set; }
public DateTime DateCreated { get; set; }
public bool IsDeleted { get; set; }
}
Any suggestions welcome.

Answer 1

You are neither eager loading the MailingList entries with the query, nor fulfulling the requirements for a lazy loading proxy so there is no way EF can populate the collection.
To allow lazy loading, change the MailingList property to be virtual to allow the EF proxy to override it.
To use eager loading, use Include() (an extension method in System.Data.Entity) in the query to specify that the MailingList should be loaded.