Sams Teach Yourself ADO.NET in 21 Days

Day 18. Building a Data Factory

Yesterday, you learned how .NET features such as inheritance can be used to create classes in the data services tier of a multi-tier application. Along the way you saw examples of both the direct and abstracted providers approaches to using .NET Data Providers. The former approach entails declaring provider-specific objects in your methods and coding directly to them, whereas the latter approach allows for the use of a ProviderFactory class that abstracts the creation of provider-specific objects. However, there is also a third approach that you can use, known as the internal data factory. This approach is more complicated and will be the focus of today's lesson.

Specifically, today you'll learn

• The purpose and ...