Question

Possible Duplicate:
Should I use #define, enum or const?
Advantage and disadvantages of #defines vs. constants?

How enum will be more useful than #define and const.
memory and code visibilty point of view and readability point of view.
can I convert (type cast) enum to array of int, If I have taken all value within integer.

Example:

    class MapPlt_clContainer { 
    public:  
    enum tagVectorType {       
    enVTAll = 0,       
    enVTPolygon,       
    enVTLines 
    }  
    };  

    tVoid MapPlt_clRender::vDrawLineClass( MapPlt_clContainer::tagVectorType* ) 

While calling function enum pass

vDrawLineClass( ClassArray_Group ); //Working

While calling array base address pass

int test[3] =  
{       
5,       
6,       
7, 
};   

vDrawLineClass( test); //Not Working

Error!!

Should it type cast it automatically? or it is compiler dependent. In my case it is giving error.

Answer 1

enum is a separate type unlike #define and the language (with the help of compiler) will help you ensure you are not mixing values of different types (even if they are of the same numerical value).

Additionally the value of an enum is available to the debugger whereas the original meaning of the #define is lost during the pre-processing time (before the code generation has even begun).

Type-casting an enum to an int is an automatic built-in process while the opposite conversion is trickier as not all the int values could be valid for your particular enum.

Modern compilers will also warn you if you have used all the possible enum‘s values in a switch statement that has no default clause, something that cannot be checked for #defines