Question

How I can use Include of the LINQ properly under MVC3?

I created .edmx file and it has all tables.

Two of them have a relashionships

UserCategories 1..0 – * Users

I guessed to use

var userCategories = db.UserCategories.Include("Users");

in order to populate Users property. But it is always empty.

(Here there is a good example how to use it. But no success.)

How do I can fix it?

P.S. POCO class

 public partial class UserCategory
    {
        public UserCategory()
        {
            this.Users = new HashSet<User>();
        }

        public string Name { get; set; } 
        public System.Guid ID { get; set; }

        public virtual ICollection<User> Users { get; set; }
    }

Answer 1

Ok, first if Users it’s empty probably it’s because your don’t have the data in the database. Now to be specific refactor your expression like this

var userCategories = db.UserCategories.Select(x => x.Users).ToList(); 

This will retrieve all the users in your database which have a relation with the table UserCategory

If you just tried to obtain the users no matter the relation with the table

var users = db.Users.ToList(); // This retrieve all the users in your database

Disclaimer: note that this expressions are heave and bring all the records of your database used carefully