DataTable Wrapper or How to decouple UI from Business logic

Question

I am using web forms, C#, Asp.net. As we all know, in this model UI and business logic are often mixed in. How do I separate these effectively?

The example I would like to use is: I have a GridView and a DataTable (GridView binds to the DataTable and DataTable is fed from the stored procedure).

I would like the GridView (UI) and DataTable (business logic) to be decoupled.

Is it worth it to write an wrapper for DataTable? Are there practical patterns that have been proved and tested that you could recommend to be followed?

If someone with experience could shed some light, that would be awesome. And, as a final note I would like to say that ASP MVC is not an option right now, so don't recommend it.

My database access layer returns a DataTable. Note that I HAVE to use this database layer as this is a company policy.

Answer 1

I'd start by decoupling the data table right into the trash can. Build a domain layer, and then some type of data access layer which deals with the DB (ORM recommended).

Then build a servicing layer which provides the data to the UI. All business logic should be within the service or the entities themself.

Answer 2

Consider implementing MVP (model view presenter) pattern. It gives you separation of biz logic through presenter interface, which also allow better unit testing capabilities. Your codebehind of aspx page is then just connector of events and getter/setter of properties. You can find it in MS pattern&practices enterprise application blocks (CAB - composite application block - if i'm not mistaking).
You can read more about it here: http://msdn.microsoft.com/en-us/magazine/cc188690.aspx
But also going from DataTable/DataSets to objects (POCO) is preferred.