I\'d like to invoke the user\'s screen saver if such is defined, in a Windows environment.
I know it can be done using pure C++ code (and then the wrapping in C# is
I think having a .Net library function that does this is highly unlikely - I'm not aware of any. A quick search returned this Code Project tutorial which contains an example of a managed wrapper which you mentioned in your question.
P/invoke exists so that you're able to access OS-specific features, of which screen savers are an example.