But from inside my code, calling ConfigurationManager::AppSettings does not seem to resolve to anything. I checked the output folder and did not see any application.exe.config that one normally expects from C# projects.
I did a little bit of research and found this app.config article for C++/CLI in CodeProject. It seems that the key is in the project property's post-build event. Specifically, you have to run the external command:
copy app.config "$(TargetPath).config"
This properly copies the config file to the object code output location where it can be read by the application.The next hurdle is converting the managed System::String^ class, that is returned by the System::Configuration methods, to the old c-style null-terminated string. This one is achieved by using the System::Runtime::Interopservices::Marshal methods. The shortest way of writing this expression that I've seen is this one from MSDN.