#define Preprocessor Directive

In C++: Define a constant:

#define UNICODE

//Check if a constant is defined:

#ifdef UNICODE

#define MessageBox MessageBoxW

#else

#define MessageBox MessageBoxA

#endif

//Undefine a constant

#undef UNICODE

In VB.NET - Define a constant:

• #Const MyConst = TRUE (FALSE defaults to undefined)
• Or in Project Properties>Compile>Advanced Compiler Settings>Custom Constants and type the custom constants, e.g.: Smartphone=TRUE, MyConst=TRUE

Check if a constant is defined:

#If MyConst = TRUE Then

'Do something

#else

'Do something

#end if