问题:

As it gives only Upper case letters, any idea how to get lower case?? If the user simultaneously pessed SHIFT+K or CAPSLOCK is on,etc, I want to get lower cases.. is it possible in this way or another??

Thanks,

回答1:

As you rightly point out, it represents a key and not upper or lower-case. Therefore, perhaps another call to ::GetASyncKeyState(VK_SHIFT) can help you to determine if the shift-key is down and then you will be able to modify the result of your subsequent call appropriately.

回答2:

Suppose "c" is the variable you put into GetAsyncKeyState().

You may use the following method to detect whether you should print upper case letter or lower case letter.

string out = "";

bool isCapsLock() { // Check if CapsLock is toggled
    if ((GetKeyState(VK_CAPITAL) & 0x0001) != 0) // If the low-order bit is 1, the key is toggled
        return true;
    else
        return false;
}

bool isShift() {  // Check if shift is pressed
    if ((GetKeyState(VK_SHIFT) & 0x8000) != 0) // If the high-order bit is 1, the key is down; otherwise, it is up.
        return true;
    else
        return false;
}

if (c >= 65 && c <= 90) { // A-Z
    if (!(isShift() ^ isCapsLock())) { // Check if the letter should be lower case
        c += 32;  // in ascii table A=65, a=97. 97-65 = 32
}
out = c;