question about macro define

[HeartFriend]

void func(UINT nOperation) { #if (nOperation == OPERATION_1) #define OPERATION(spObj, nParam) fun1(spObj, nParam) #elif (nOperation== OPERATION_2) #define OPERATION(spObj, nParam) func2(spObj, nParam) #elif (nOperation== OPERATION_3) #define OPERATION(spObj, nParam) func3(spObj, nParam) nFrameNo) #else #define OPERATION(spObj, nParam) #endif .... OPERATION(spObj, n) // whatever nOperation be, it always call fun1,why??? }

[Jose Lamas Rios]

Macros don't work at runtime; they are processed before compilation. Try something like this instead:

void func (UINT nOperation)
{
   switch (nOperation)
   {
      // [edited - Thanks DavidCrow] case default:
      default:
         break;
 
      case OPERATION_1:
         fun1(spObj, nParam);
         break;
 
      case OPERATION_2:
         fun2(spObj, nParam);
         break;
 
      case OPERATION_3:
         fun3(spObj, nParam);
         break;
   }
}

-- jlr http://jlamas.blogspot.com/[^]

[S Senthil Kumar]

:omg: You've mixed up precompiler directives with code. Macro expansion (and execution of other precompiler directives) happen before code is compiled. Regards Senthil _____________________________ My Blog | My Articles | WinMacro

[David Crow]

Jose Lamas Rios wrote: case default: No case needed here.

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"Ideas are a dime a dozen. People who put them into action are priceless." - Unknown

[Jose Lamas Rios]

DavidCrow wrote: Jose Lamas Rios wrote: case default: No case needed here. Yep, you are right. -- jlr http://jlamas.blogspot.com/[^]