Detecting that the user is away from the PC with .NET

Question

I have a desktop application in which I would like to know two things:

1. Is the user currently on the PC (more specifically, is he giving any input to the PC), s

Answer 1

Here is the code to detect if a screen saver is running. See this for more details

const int SPI_GETSCREENSAVERRUNNING = 114;

[DllImport( "user32.dll", CharSet = CharSet.Auto )]
private static extern bool SystemParametersInfo( 
   int uAction, int uParam, ref bool lpvParam, 
   int flags );


// Returns TRUE if the screen saver is actually running
public static bool GetScreenSaverRunning( )
{
   bool isRunning = false;

   SystemParametersInfo( SPI_GETSCREENSAVERRUNNING, 0, 
      ref isRunning, 0 );
   return isRunning;
}