Detect keyboard input after windows recognition of the key

Question

I am building a program that would print out the pressed buttons' values on the screen. I need it to work also when the program's window is not active. I tried using GetAsyncKeyState(int), which works fine. However, I can attach certain strings to keys, but it doesn't work for all types of keyboards (for example, on english keyboards shift+2 is @, while on mine its not). How can I detect post-processing of the key input that is done by Windows (the character that is printed on the screen when writing in Notepad)?

Answer 1

Try the OemKeyScan function. With yours you should have the scancode (eg the "2" key has a given scancode that is always the same depending on position on the keyboard, eg 17 for the "2" key):

    int whichscancode= 17;
    if (key_with_shift)
        whichscancode|= (1<<16);  // shifted values with 1<<16

    for (i=0; i<256; i++) {
            int scan= ::OemKeyScan(i);  // try all characters for a matching scancode
            if (scan==whichscancode) {
                // i here is the ascii code of the key on that position
                printf("on that scancode is character %c\n", (char)i);
            }
    }