CODEWITHSUNDEEP
c++classenums
ChiggenWingz
ChiggenWingz

Reputation: 471

How do I use the Enum value from a class in another part of code?

Coming from a C# background from a night course at a local college, I've sort of started my way in C++. Having a lot pain getting used to the syntax. I'm also still very green when it comes to coding techniques.

From my WinMain function, I want to be able to access a variable which is using an enum I declared in another class.

(inside core.h)
class Core
{
    public:
    enum GAME_MODE
    {
        INIT,
        MENUS,
        GAMEPLAY
    };
    GAME_MODE gameMode;

    Core();
    ~Core();
    ...OtherFunctions();
};

(inside main.cpp)
Core core;
int WINAPI WinMain(...)
{
    ... startup code here...

    core.gameMode = Core.GAME_MODE.INIT;

    ...etc...
}

Basically I want to set that gameMode to the enum value of Init or something like that from my WinMain function. I want to also be able to read it from other areas.

I get the error...

expected primary-expression before '.' token

If I try to use core.gameMode = Core::GAME_MODE.INIT;, then I get the same error.

I'm not fussed about best practices, as I'm just trying to get the basic understanding of passing around variables in C++ between files. I'll be making sure variables are protected and neatly tucked away later on once I am use to the flexibility of the syntax.

If I remember correctly, C# allowed me to use Enums from other classes, and all I had to do was something like Core.ENUMNAME.ENUMVALUE.

I hope what I'm wanting to do is clear :\ As I have no idea what a lot of the correct terminology is.

Upvotes: 38

Views: 68989

Answers (1)

Martin B
Martin B

Reputation: 24140

Use

core.gameMode = Core::INIT;

The individual values of an enumeration are scoped not within that enumeration but at the same level as the enumeration itself. This is something that most other languages (including C#) do differently, and C++0x will allow both variants so that there,

core.gameMode = Core::GAME_MODE::INIT;

will also be legal.

In addition, the strongly typed enums that will be added in C++0x (enum class) will put the enum values only within the scope of the enum (i.e. as in C#); this solves the problem you noted in your comment that for "normal" enums, the identifiers for enum values need to be unique across all enums defined in the same scope.

Upvotes: 49

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