Question

I’m trying to use the awsome EF5 with code first – where I need to make a many-to-many table with extra fields.

I’ve got a products table, orders table and need a table of products that are in orders with a “size” field.

What I’ve done is created a new class of “ProductOrder” that is the connection table between them, and made a reference.

It WORKS when creating a new order, but is not working when fetching an order – it doesn’t get the connected orders (that are present in the DB after the insertion).

Ideas why? 🙂

My Classes are:

public class Order
{
    public int ID { get; set; }
    ...
    public ICollection<ProductOrder> Products { get; set; }
    public Order()
    {
        Products = new HashSet<ProductOrder>();
    }
}

public class Product
{
    public int ID { get; set; }
    public ICollection<ProductOrder> Orders { get; set; }
}

public class ProductOrder
{
    public int ID { get; set; }
    public int ProductID { get; set; }
    public int OrderID { get; set; }
    public int Size { get; set; }

    [ForeignKey("OrderID")]
    public Order order { get; set; }

    [ForeignKey("ProductID")]
    public Product product { get; set; }
}

and in onModelCreating

    modelBuilder.Entity<Order>()
        .HasMany(p => p.Products)
        .WithRequired(o => o.order)
        .HasForeignKey(o => o.OrderID);

    modelBuilder.Entity<Product>()
        .HasMany(o => o.Orders)
        .WithRequired(p => p.product)
        .HasForeignKey(p => p.ProductID);

Answer 1

Your navigational properties need to be virtual