Winforms - best directory / project structure

Question

Wanted to see peoples thoughts on best way to organize directory and project structure on a project / solution for a winforms C# app.

Most people agree its best to seperate view, business logic, data objects, interfaces but wanted to see how different people tackle this. In addition, isolate third party dependencies into implementation projects and then have interface exported projects that consumers reference

View.csproj

BusinessLogic.csproj

Data.csproj

CalculatorService.Exported.csproj (interfaces)

CalculatorService.MyCalcImpl.csproj (one implementation)

CalculatorService.MyCalcImpl2.csproj (another implementation)

Also, in terms of folder structure, what is better nesting:

Interfaces
---IFoo
---IData
Impl
---Foo
---Data

or

Product
---Interfaces/IProduct
---Impl/Product
Foo
---Impl/Foo
---Interfaces/IFoo

All trying to push for decoupled dependencies on abstractions and quick ability to changed implementations.

Thoughts? Best practices?

Answer 1

For me it depends on the model I'm following. If I'm using MVC it would be

Project
-Models
-Controllers
-Views

Or for MVP it would be

Project
-Models
-Presenters
-Views

Under the views I seperate them into namespaces relevant to the controllers, i.e. if I have a controller to handle inventory transactions I might have it as

Project
-Models
--Inventory
-Controllers
--Inventory
---TransactionsController.cs
-Views
--Inventory
---Transactions
----EditTransactionsView.dfm

For interfaces I put the interface in the same directory as the implementations.

Answer 2

Bit of a late answer but may as well chime in.

I have been personally using folders based on the actual type of item it is. For example:

- Project
    + Forms
    + Classes
    + UserControls
    + Resources
    + Data

So I end up with:

new Forms.AboutForm().ShowDialog();
Controls.Add(new Controls.UberTextBox());