I believe that to share the same code base, you need to compile your functions to a DLL and then reference the DLL in your other project.
>I have a Function.vb file that I put in my VS.NET framework. That file need to be added to existing VS projects. When I do an Add Existing Item, the file is copied into the project directory. So, if I modify the main file, the other file is not updated. How can I make a live reference?
Hector Correa