Macro definitions and Enumerations

Macro definition:

There are three benefits to using a string instead of a data at the beginning of the code

1. Make some data meaningful

#define KOUT-1

#define Kappsecret KDJGHHGF

#define Kappkey 123456

2, easy to use, similar to the meaning of the restrained function

#define KADD (a B) ((a) + (b))

#define Kmultiple (A, a) ((a) * (b))

3, the output log switch

#if 1

#define DEBUG (x) printf ("%s\n", X)

#else

#define DEBUG (x)

#endif

Enumeration:

1, define an enumeration, the type name is Kanimalcategory

typedef enum{

Kanimalcategoryburu = 2,//Default starting from 0

Kanimalcategorymaoke = 5,//The latter will add 1 above the former, if not assigned

Kanimalcategoryfeiqin = 7,//

Kanimalcategoryzoushou//8

2. Differences between macro definitions and enumerations

A macro definition is a value/expression, not a type

An enumeration is a type that can define a variable of an enumeration type

Macro definitions and Enumerations