How to Separate the DAL Layer and BLL Layer in a a C# application

Link to Class diagrma Layering
Link to Class Diagram Mail System.
NClass 2.0 or higher is needed to read the file.  NClass Website

In this article we are going to discuss how to separate the Data Access Layer (DAL) form the Business Logic Layer (BLL) using

1) The Abstract Factory Pattern
2) The Model Provider Pattern
3) Reflections


On the Class Diagram Mail System you will find many notes on how to separate the BLL from the DAL
I will first comment on the Class diagram you will find on the link. After I will develop an applicaton. This is a working in progress. As usual if you have any suggestion or improvement, just add a comment.