"using" of two different libraries with almost identical functions

Question

I'm consuming a SOAP web service. The web service designates a separate service URL for each of its customers. I don't know why they do that. All their functions and parameters are technically the same. But if I want to write a program for the service I have to know for each company is it intended. That means for a company called "apple" i have to use the following using statement:

using DMDelivery.apple;

and for the other called "orange"

using DMDelivery.orange;

But I would like to my program to work for all of them and have the name of the company or the service reference point as a parameter.

Update: If I have to write a separate application for each customer then I would have to keep all of them updated with each other with every small change and that would be one heck of an inefficient job as the number of customers increase.

Can anyone think of a solution? I'll be grateful.

Answer 1

If you have a base contract (interface) for all your services you can use a kind of factory to instantiate your concrete service and only have a reference to your interface in your client code (calling code).

//service interface
public interface IFruitService{
  void SomeOperation();
}

//apple service
public class AppleService : IFruitService{
  public void SomeOperation(){
    //implementation
  }
}

Having for example a kind of factory class (you can put your using statements here)

public static class ServiceFactory{
  public static IFruitService CreateService(string kind){
    if(kind == "apple")
      return new AppleService();
    else if(kind == "orange")
      return new OrangeService();
    else
      return null;
  }
}

And in your calling code (you just add an using statement for the namespace containing your interface):

string fruitKind = //get it from configuration
IFruitService service = ServiceFactory.CreateService( fruitKind );
service.SomeOperation();

You can also use the Dependency Injection principle.