msbuild: set a specific preprocessor #define in the command line

Question

In a C++ file, I have a code like this:

#if ACTIVATE
#   pragma message( \"Activated\" )
#else
#   pragma message( \"Not Activated\")
#endif

I

Answer 1

It should probably be:

#ifdef ACTIVATE
#   pragma message( "Activated" )
#else
#   pragma message( "Not Activated")
#endif