Convert Windows application to Class Library(dll)

First, identify the Business Logic, Data Layer & Presentation/Application Layer logic in your application. Later, keep only the Presentation layer logic in your Windows Forms. In the next step, add a Class Library type of Project to your Solution. Move all the Business Layer logic to the Business Layer project. I would suggest if you could segregate the Data Layer as well, it would be good and code would be more maintainable. Later on, you would have to set the Application Layer Project i.e. Windows Form Project as start-up Project, unless your application has multiple start-up projects. Then, build the Class Library and add the refrence to Windows Form Project. Now, in the place where you had written your business level logic, you would have to replace it with the function calls to the Business Layer i.e. the Class Library functions. This would reduce the code redundancy and the same peice can be easily reused by sharing the DLL.

I hope this explanation is of some use to you.

To execute your Class Library Logic in Visual Studio, you need to:

1. Add a Windows Application project to the solution.
2. Create a Reference from the new project to the existing Class Library Project.
3. Add Code to the new Windows Application Project that invokes the existing class library project. E.g. Stick a button on a form and put the code you need behind that.

If any of these steps need more explaination then I can go into more detail.

-Rd