How to detect version of MS Visual Studio or compiler in compilation time?

To do this you should use _MSC_VER define like in this code:
#if _MSC_VER >= 1400 // this is Visual C++ 2005
#elif _MSC_VER >= 1310 // this is Visual C++ .NET 2003
#elif _MSC_VER > 1300 // this is Visual C++ .NET 2002