Macro definition & CodeBlocks & amp; Glib

I,In the gcc Parameter
-Dmacro is equivalent to # define macro-Dmacro = value in the Code. # define macro value-Umacro is equivalent to # undef macro in the code.

II,Macro definition,Slash ("\") Is used to resume rows,"#"Is used to convert a parameter to a string, which is to add double quotation marks to the parameter."##"Is used to connect the first and second parameters and convert them into a string,"# @ "Adds single quotation marks to parameters. For example#define Conn(x,y) x##y #define ToChar(a) #@a  #define ToString(x) #x int n = Conn(123,456);   Result n = 123456; char* str = Conn("asdf", "adf")Result str ="asdfadf"; char a = ToChar(1);ResultA ='1'; char* str = ToString(123132);ResultStr ="123132";3. Use the-D macro defined as a string in CodeBlocks. If a Bug exists, for example, when the log macro of G_LOG_DOMAIN of Glib is defined, when-DG_LOG_DOMAIN = "plugin_dispatch" is added to the compilation option, the system prompts plugin_dispatch is undefined. This is obviously because double quotation marks are discarded during macro preprocessing. The solution is to use gmacros. h # define partition (contents) # contentsG_LOG_DOMAIN = G_STRINGIFY_ARG (plugin_dispatch) Build prompt syntax error near unexpected token '(' changed to G_LOG_DOMAIN = "plugin (plugin_dispatch)" build successful