first thank to you for your reply.
let me to explain problem with an example(very very simple example).
sepose you have a table in database (say it Customers), that it has 3 fields (id,firstName,lastName).
i want to model it, with EDM(Ado.net Entity Data Model).
for this,i create a ado.net entity data model item(a file with edmx extension) by right click on the project in solution explorer window and choose add new item. right?
i create my edmx base on existing my data base. result is a edmx file that contains a object (Customers) that maped to Customers table in my Database.
and then i can get Customers with creating query with Linq To Entity and bind data to controls in the form.
all of these works fine. but my application will be not in N-Layer Architecture. i want to know whwn i want to creat this application in N-Layer architecture, what kind of layers i should create and what objects are exist in what layers?
the edmx files must be create in DL(Data access layer)? or in BL?
when i want to athenticate user inputs, where classe i should create and where i should perform athentication ruls? in BLL, but how?
can you explain the above example,in 3-teri application?
one layer for presentation (it can be windows form application).
one tier for Data access ( i think the edmsx files must be locate in this layer)
one layer for application ruls ( sepose the customer first name and last name must be checked for correct data. for example the name and family can not be contains numberic inputs. and others ruls such as length checking of inputs and ...)
thanx so much