private extern static uint Win32GetLayeredWindowAttributes (IntPtr hwnd, out COLORREF pcrKey, out byte pbAlpha, out LayeredWindowAttributes pwdFlags);
private extern static uint Win32SetLayeredWindowAttributes (IntPtr hwnd, COLORREF crKey, byte bAlpha, LayeredWindowAttributes dwFlags);
public static extern bool SetLayeredWindowAttributes(IntPtr hWnd, UInt32 crKey, byte bAlpha, LayeredWindowAttributes dwFlags);
private static extern bool User32_SetLayeredWindowAttributes(IntPtr hWnd, int crKey, byte bAlpha, LayeredWindowAttributes dwFlags);
public static extern bool GetLayeredWindowAttributes(IntPtr hwnd, out uint crKey, out byte bAlpha, out LayeredWindowAttributes dwFlags);