#650 – Getting Information About Keyboard Keys from Any Method

You can use the KeyEventArgs.KeyboardDevice property within a keypress handler to get information about any keyboard key.  For example:

private void TextBox_PreviewKeyDown(object sender, KeyEventArgs e)
{
    Console.WriteLine(string.Format("Toggle info: Caps Lock:{0}, Scroll Lock: {1}, Num Lock: {2}",
        e.KeyboardDevice.IsKeyToggled(Key.CapsLock),
        e.KeyboardDevice.IsKeyToggled(Key.Scroll),
        e.KeyboardDevice.IsKeyToggled(Key.NumLock)));
}

You can also access the same KeyboardDevice object from any method, using the Keyboard.PrimaryDevice property (found in System.Windows.Input). This property will refer to an instance of a KeyboardDevice object.

        public void MyFunctionToGetKeyInfo()
        {
            Console.WriteLine(string.Format("Toggle info: Caps Lock:{0}, Scroll Lock: {1}, Num Lock: {2}",
                Keyboard.PrimaryDevice.IsKeyToggled(Key.CapsLock),
                Keyboard.PrimaryDevice.IsKeyToggled(Key.Scroll),
                Keyboard.PrimaryDevice.IsKeyToggled(Key.NumLock)));
        }