Implementin Three-Tier App.

  • Thread starter Thread starter Anibal
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A

Anibal

Hi,
I'm learning about three-tier programing and i want to implement this in a
simple windows forms Application (not web), i'm using an Access 2000 Data
Base, the objective of my application is to stores data from cd's into the
data base, so i have 4 related tables, ("CdCategories",
"Cds","Folders","Files"). I want to use Typed Data Classes, so i made one
class for each table and one Typed DataSet for each relation (each of this
typed datasets contains a pair of datatables with a defined DataRelation,
for example a "Folder-Files" dataset). The problem that i have is that i
don't know exactly how to implement all this especially when creating the
BLL and the DAL layers.
I've allready tryed a couple of thing but i allways fall into a death end.
I tried to find examples on the web but i've only found web applications
related examples.
If any of you could give me some ideas i`ll be thanksfull.

Thank you.
 
Thanks for your help,

I've read the article, but i think my problem is more basic than using
remoting to implement in my app.
What i don't know is where to put my my Strongly Typed Classes. For example,
i've tried puting all the typed classes in my DAL in order to be called by
the BLL to create all data objects and manipulate them.
But the problem that i have is that with this aprouche i don't know how to
comunicate the BLL with the client layer without loosing a lot of
flexibillity in code, becouse of the fact that the client layer can't see
directlly the typed classes that the BLL is using.
So i would have to re-implement the DAL typed classes in the BLL to
comunicate with the client layer (or something).
Another idea was to put all typed classes in the BLL, but i have problems
when comunicating with the DAL, becouse of the same reason, the DAL doesn't
know the typed classes, and i can't (for example) cast a generic DataSet to
a typed DataSet, so i can't have the BLL calling the DAL and saing "Give me
a generic DataSet with this or that data from the data base" and then
converte it to a strongly typed DataSet with CType function.
So i came out with the idea that the three layers should "see" the typed
data classes, but this would throw away all the idea of the desing itself,
becouse if i want to update the app later, i will have to modify all
three-layers.
 
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