I'm new to the .net world, but I've been developing native Win32 3-tier applications for some time now.

I'm not sure what are my options to develop this kind of applications in .NET, so I'd like to know what's the advantages of using LLBLGen Pro for this purpose.

Basically, what I'm looking for is to have a WinForms thin client that requests objects from a middle tier. This middle tier could filter the list of objects before sending to the client according to logged user rights. When the changes an object, I want to send these changes to the middle tier, that will decide what to do. The thin client will never connect to the databse, only the middle tier will.

Any comments are appreciated. Thanks in advance.

3-Tiers architecture is the same whether you are using .Net or not, it's just the same concept. And it depends whether you have a Data Access Layer, or you call the database as the 3rd Layer.

Anyway, LLBLGen Pro creates the DAL and the Low Level Businnes Layer for you (business objects). Please refer to the LLBLGen Pro manual "Concepts -> N-tier development"

Thanks. Now I have more questions:

My idea is to have the BL and DAL running on the same server (or server farm) along with the database.

1 - Can I have some validations on the client and some validations on the BL before sending the object to the database?

2 - When I modify an object and want to save, what is sent to the BL? Only the changed values or the entire object? If I send a list of objects to be saved, only the changed ones are sent?

The client will send the entire object/collection to the BL and to the DAL, but the DAL will only issue update statements for the changed entities, and only for the changed fields.

You can have UI/client validation, using normal .NET validation controls, and the in the BL/DAL you can use the LLBLGen Pro validation techniques.