Which Of The Two Design Patterns Should I Implement In A 3-tier .Net Application

Sep 22, 2010

I'm trying to decide which of the two factory patterns I should use in my Asp.Net applications:

1 : All DAL providers derive from same abstract base class DepartmentsProvider, which defines public interface of the class ( all the necessary CRUD methods for which derived classes (providers ) provide a concrete implementation ). BLL layer instantiates correct provider by calling DepartmentsProvider.Instance:

public abstract class DepartmentsProvider
static private DepartmentsProvider _instance = null;
/// <summary>[code]....

In first case we implement new provider by deriving from DepartmentsProvider class, while in second case new provider is implemented by deriving from DBProviderFactory. What are pros and cons of each implementation?

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