objective-c concatenation of strings in a macro

Official server
#define Api_domain @ "www.online.com"
Test server
#define DOMAINXX @ "192.168.0.10"


#define API_SYSTEM @ "/http" [email protected] "/system/"
#define API_USER @ "/http" [email protected] "/user/"


API_SYSTEM macro expands to: @ "/http" @ "www.online.com" @ "/system/"
The compiler will automatically connect the characters together for the purpose.


C-Language implementation:
Official server
#define Api_domain "Www.online.com"
Test server
#define DOMAINXX "192.168.0.10"


#define API_SYSTEM "/http" Api_domain "/system/"

#define API_USER "/http" Api_domain "/user/"

Reference:
http://stackoverflow.com/questions/8844981/ How-to-expand-a-macro-into-nsstring-without-using-any-string-concatenation-at-ru

Http://stackoverflow.com/questions/798221/c-macros-to-create-strings

objective-c concatenation of strings in a macro