Question

I have the following Customer class:

public class Customer : EntityBase<Customer>
{
    public virtual int ID { get; set; }
    public virtual CustomerType CustomerType { get; set; }

    public virtual string CompanyName { get; set; }
    public virtual string FirstName { get; set; }
    public virtual string LastName { get; set; }

    public virtual ICollection<Address> BillingAddresses { get; set; }
    public virtual ICollection<Address> ShippingAddresses { get; set; }
}

The Address class looks like this:

public class Address : EntityBase<Address>
{
    public virtual int ID { get; set; }
    public virtual AddressType AddressType { get; set; }
    public virtual bool IsDefault { get; set; }
    public virtual string Name { get; set; }
    public virtual string Line1 { get; set; }
    public virtual string Line2 { get; set; }
    public virtual string Line3 { get; set; }
    public virtual string City { get; set; }
    public virtual string State { get; set; }
    public virtual string ZipCode { get; set; }
    public virtual string Country { get; set; }

    public virtual int CustomerID { get; set; }
    public virtual Customer Customer { get; set; }
}

I want to be able to have multiple of each kind of address on the customer class, but I am having a hard time figuring that out.

I would like to end up with something like this to get to the default address for each type.

public Address DefaultBillingAddress
{
    get
    {
        return BillingAddresses.First(x => x.IsDefault == true);
    }
}

The problem I am having is how do I tell the difference between the AddressType enum on each ICollection?

Answer 1

You are capturing the concept of “address type” in two different ways.

You have your AddressType enum on Address, and you also have separate

public virtual ICollection<Address> BillingAddresses { get; set; }
public virtual ICollection<Address> ShippingAddresses { get; set; }

It’s certainly possible with this model to end up with something in BillingAddresses with AddressType.Shipping and vice versa.

I would suggest simplifying your object model to

public virtual ICollection<Address> Addresses { get; set; }

and providing helper methods on Customer that return Billing and Shipping addresses, respectively, from Addresses.

Having said that, I’m not sure what you mean by

The problem I am having is how do I tell the difference between the AddressType enum on each ICollection?

Each ICollection should reference the same AddressType enum.

Using my suggested approach, you could write

public Address DefaultBillingAddress
{
    get
    {
        return Addresses
         .First(x => x.IsDefault == true && x.AddressType == AddressType.Billing);
    }
}