Hi,

I am new to the architecture. But I am well versed with using LLBLGen in my previous project. So In my new project I suggest LLBLGen to my new client and they accepted that. I am also delivered the DAL layer for my project. My project environment is WPF 4.0, Oracle 11g, MV VM.

My client entrust me to create a BL for my project. Since I am not well versed with the design patterns and MVVM, I am struggling to arrive at a design for my BL. I didn't find a sample with LLBLGen and WPF in n-tier architecture. Is anybody can help on this so that I can have something to go at for creating a BL.

To be honest, your question is so general that it is hard for us to give any sensible answer. My suggestion would be to have a read up on the internet of the different ways of structuring n-tier applications, and come back to us with any more specific, LLBLGen related questions.

We're always happy to help, but do need something specific to get our teeth into

Matt

Moved to architecture.

For BL layer my collegue's suggestion is to use DAL entities in BL (A BL object will contains LLBL Entity and EntityCollections as its properties) also and return it to UI. But I didn’t like that as it will strongly couple the DAL to UI.

Do you have a sample implementation of BL based on LLBLGen entities in which we map BL entites to LLBL entities and viseversa?

How does it strongly couple the DAL to the UI any more than using POCO entities ? The UI still has to have the knowledge of the structure of the entities that it will be working with. What it does do is strongly couple both layers to LLBLGen - you need to decide for yourself if this is acceptable for you.

Personally I've never had a problem with it, the advantages gained (ie all of the nice stuff that the LLBLGen entities do for you, such as change tracking and graph management, and the fact that you don't have to continually translate your DAL entities to your UI entities and back again) far outweigh the disadvantages that come with the additional coupling.

Sorry, but I don't think any of the samples in the download area are n-tier. They are designed to demonstrate specific language features rather than overall architechture.

Matt