I’m using Visual Studio 2010 Pro to build a solution that contains two projects. Project A contains most of my source code, while Project B is intended to run independently, but must use some of the source code contained in Project A.
Under the current configuration, Project A is contained as a reference within Project B. I’d like to be able to build and maintain versions of each project independently, but it appears that when I build the entire solution, ProjectB.exe cannot run without ProjectA.exe in the same local directory. I would think and hope that when the .exe binaries are compiled that all of their dependencies are packaged within each, but that appears not to be the case. In fact, any attempt to run ProjectB.exe while ProjectA.exe is not present results in a System.IO.FileNotFoundException.
Is there a way to build a version ProjectB.exe that runs independently and avoids code duplication?
In cases where you want common code, the best solution is to break out the common classes into a third assembly to serve as a library. (As per Adriano’s suggestion.) The other option he hints at is to use the “as link” option when using the “add existing file” to the second project.
If you don’t know where it is, use the “Add existing file” option, then in the dialog box to select the file, the “Add” button has a drop-down selection where you can select “As Linked File” (or something to that effect.)
This allows you to compile the same classes into multiple projects. But keep in mind that the namespacing for the linked file cannot be changed for the second project. If the namespace was “ProjectA.Domain”, this is how you need to access it in Project B. This was a useful trick for Silverlight projects back before the multi-platform assemblies were introduced.