Need help turning this if sequence into a switch case

How do you turn this....

Code:

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//macros to read the keyboard asynchronously
#define KEY_DOWN(vk_code) ((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)
#define KEY_UP(vk_code)((GetAsyncKeyState(vk_code) & 0x8000) ? 1 : 0)

        if (KEY_DOWN(VK_RIGHT))
        {
                right = right + 1;
                left = left + 1;
        }
        if (KEY_DOWN(VK_LEFT))
        {       
                right = right -1;
                left = left - 1;
        }
        if (KEY_DOWN(VK_UP))
        {
                top = top - 1;
                bottom = bottom - 1;
        }
        if (KEY_DOWN(VK_DOWN))
        {
                bottom = bottom + 1;
                top = top + 1;
        }

---

into a switch statment....

This was my attempt at it but I could not figure out the whole call to KEY_DOWN aspect

Code:

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        switch (KEY_DOWN())
        {
        case VK_RIGHT;
                right = right + 1;
                left = left + 1;
                break;
        case VK_LEFT;
                right = right -1;
                left = left - 1;
                break;
        case VK_UP;
                top = top - 1;
                bottom = bottom - 1;
                break;
        case VK_DOWN;
                bottom = bottom + 1;
                top = top + 1;
                break;
        default:
                break;
        }

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this is just a wild guess, but have you tried finding out the return type of KEY_DOWN? in your if statements you have KEY_DOWN(VK_UP) and so on, they don't return those values do they?