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Get key press in windows console

I found this piece of code online:

CHAR getch() {
    DWORD mode, cc;
    HANDLE h = GetStdHandle( STD_INPUT_HANDLE );

    if (h == NULL) {
        return 0; // console not found
    }

    GetConsoleMode( h, &mode );
    SetConsoleMode( h, mode & ~(ENABLE_LINE_INPUT | ENABLE_ECHO_INPUT) );
    TCHAR c = 0;
    ReadConsole( h, &c, 1, &cc, NULL );
    SetConsoleMode( h, mode );
    return c;
}

Using it like:

while(1) {
    TCHAR key = getch();
}

I am able to get numeric, alphabetic even return key presses. But am not able to get escape or other functional keys like control, alt. Is it possible to modify it to detect also these keys?

like image 430
user1806687 Avatar asked Jan 05 '23 21:01

user1806687


1 Answers

If stuff like control and alt keys, these are virtual key strokes, they are supplements to characters. You will need to use ReadConsoleInput. But you will get it all, the mouse also. So you really need to filter and return a structure from the call so you know if it is the likes of ctrl-A Alt-A. Filter repeats if you don't want them.

This may need work, don't know what you are after...

bool getconchar( KEY_EVENT_RECORD& krec )
{
    DWORD cc;
    INPUT_RECORD irec;
    HANDLE h = GetStdHandle( STD_INPUT_HANDLE );

    if (h == NULL)
    {
        return false; // console not found
    }

    for( ; ; )
    {
        ReadConsoleInput( h, &irec, 1, &cc );
        if( irec.EventType == KEY_EVENT
            &&  ((KEY_EVENT_RECORD&)irec.Event).bKeyDown
            )//&& ! ((KEY_EVENT_RECORD&)irec.Event).wRepeatCount )
        {
            krec= (KEY_EVENT_RECORD&)irec.Event;
            return true;
        }
    }
    return false; //future ????
}

int main( )
{
    KEY_EVENT_RECORD key;
    for( ; ; )
    {
        getconchar( key );
        std::cout << "key: " << key.uChar.AsciiChar
            << " code:  " << key.wVirtualKeyCode << std::endl;
    }
}

ReadConsoleInput function

INPUT_RECORD structure

KEY_EVENT_RECORD structure

Virtual-Key Codes

like image 199
lakeweb Avatar answered Jan 07 '23 11:01

lakeweb