Question

I have a class in one application – that I cannot change (legacy) – that is inside of a assembly (DLL file):

public class ShippingMethod
{
    public string ShipMethodCode { get; set; }
    public string ShipMethodName { get; set; }
    public decimal ShippingCost { get; set; }

    public List<ShippingMethod> GetAllShippingMethods()
    {
    ......
    }
}

I have a second application that is referencing that assembly (DLL file) and needs to populate a drop-down with all the Shipping Methods. Ex: “UPS – $3.25”

The issue is that it needs to be using the correct format for different currencies. Ex: $3.25 or 3.25€ depending on a parameter called CountryID.

I have written a function String DisplayMoney(Decimal Amount, Integer CountryID) that will return the correct format of the amount.

Now I need to apply this function to every shipping method and save it into a new list.
What is the best way to do this?

I can create another class called LocalizedShippingMethods as follows:

public class LocalizedShippingMethod
{
    public ShippingMethod ShipMethod { get; set; }
    public string LocalizedShippingCost { get; set; }
}

Is this the best way to accomplish this? Is there a better way to do this using inheritance? And if I use inheritance, how do I get the values from the first LIST into the NEW LIST?

Answer 1

That is indeed a good method of doing it. You can use a pretty quick Linq query to pull the old List into the new one:

List<LocalizedShippingMethod> Translate(List<ShippingMethod> oldList)
{
  return oldList.Select(a => new LocalizedShippingMethod
     {
         // Initialize properties according to however you translate them
     }).ToList();
}

Additionally, to make this more streamlined and obvious, you could do any of the following to aid in the translation:

• Create a constructor for LocalizedShippingMethod that takes in a ShippingMethod and properly sets the properties
• Create a static method on LocalizedShippingMethod that takes in a ShippingMethod and returns an initialized LocalizedShippingMethod
• Create an operator on LocalizedShippingMethod that converts from a ShippingMethod
• Create an extension method on ShippingMethod, call it ToLocalized() that returns a LocalizedShippingMethod