在C++中连接#define

Question

我有类似的东西:

#define BASE_FOLDER = "Resources"
#define PREFERENCE_FILE_NAME = "AppPreferences.txt"
#define SPLASH_FILE_NAME = "Splash.png"

#define PREFERENCE_PATH = ".\\" + BASE_FOLDER + "\\" + PREFERENCE_FILE_NAME
#define SPLASH_PATH = ".\\" + BASE_FOLDER + "\\" + SPLASH_FILE_NAME

并且编译器在使用PREFERENCE_PATH时抛出错误.

expecting primary expression before = token.

这些都在我做的时候起作用

#define PREFERENCE_PATH = ".\\Resources\\AppPreferences.txt"
#define SPLASH_PATH = ".\\Resources\\Splash.png"

我究竟做错了什么？

Answer 1

摆脱等号.预处理程序定义不使用等号.

然后摆脱这些优势.当你并排放置字符串文字而没有加号时,它们会串联起来.强调文字,因为这是一个编译时功能,只适用于双引号文字,如"foo" "bar"→ "foobar".它不适用于变量.

#define BASE_FOLDER          "Resources"
#define PREFERENCE_FILE_NAME "AppPreferences.txt"
#define SPLASH_FILE_NAME     "Splash.png"

#define PREFERENCE_PATH ".\\" BASE_FOLDER "\\" PREFERENCE_FILE_NAME
#define SPLASH_PATH     ".\\" BASE_FOLDER "\\" SPLASH_FILE_NAME