Preprocessors: #define

Applies To: C++Builder 1 or higher
Category: C++ Language

The #define directive causes the compiler to replace one piece of text with another:

 

#define text_1 text_2

 

For example, if you want to replace VALUE with 100, you can use:

 

#define VALUE 100

x = VALUE;

 

You can also create function macros with #define:

 

#define DOUBLE(x) ((x)*2)

 

It is important to parenthesize the macro function and the parameters used in it to make sure that they work properly.

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