Making the Game Engine - C# Game Programming: For Serious Game Creation - page 285

{
[DllImport("User32.dll")]
public static extern short GetAsyncKeyState(int vKey);
Control _openGLControl;
public KeyPressEventHandler KeyPressEvent;
class KeyState
{
bool _keyPressDetected = false;
public bool Held { get; set; }
public bool Pressed { get; set; }
public KeyState()
{
Held = false;
Pressed = false;
}
internal void OnDown()
{
if (Held == false)
{
_keyPressDetected = true;
}
Held = true;
}
internal void OnUp()
{
Held = false;
}
internal void Process()
{
Pressed = false;
if (_keyPressDetected)
{
Pressed = true;
_keyPressDetected = false;
}
}