How to find out if the left shift or right shift key has been pressed down …
Add this declaration.
[DllImport("user32")]
public static extern short GetKeyState (Keys VirtKey);
On your KeyDown event, you can check which shift key has been pressed down in this way:
bool LShiftPressed = ((GetKeyState(Keys.LShiftKey) & 256)==256);
bool RShiftPressed = ((GetKeyState(Keys.RShiftKey) & 256)==256);
