Нужна программа, которая устанавливает обои на рабочий стол

using System.Runtime.InteropServices;

public enum SPI : uint
{
   SPI_GETSCREENSAVEACTIVE = 0x0010,
   SPI_SETSCREENSAVEACTIVE = 0x0011
}
public enum SPIF : uint
{
   None = 0x00,
   SPIF_UPDATEINIFILE = 0x01,
   SPIF_SENDCHANGE = 0x02,
   SPIF_SENDWININICHANGE = 0x02
}
[DllImport("user32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool SystemParametersInfo(SPI uiAction, uint uiParam, ref uint pvParam, SPIF fWinIni);
[DllImport("user32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool SystemParametersInfo(SPI uiAction, uint uiParam, uint pvParam, SPIF fWinIni);

uint vParam = 0;
if (SystemParametersInfo(SPI.SPI_GETSCREENSAVEACTIVE, 0, ref vParam, SPIF.None))
{
   if (vParam == 1)
       MessageBox.Show("Screensaver is enabled");
   else
        MessageBox.Show("Screensaver is disabled");
}
else
    MessageBox.Show("Error!");

if (SystemParametersInfo(SPI.SPI_SETSCREENSAVEACTIVE, 0, 0, SPIF.None))
{
   MessageBox.Show("Screensaver has been disabled");
}
else
    MessageBox.Show("Error!");

SystemParametersInfo(SPI.SPI_SETSCREENSAVEACTIVE, 1, 0, SPIF.None);

SystemParametersInfo(SPI.SPI_SETSCREENSAVEACTIVE, 1, "Goal.bmp", SPIF.None);

SystemParametersInfo(SPI.SPI_SETSCREENSAVEACTIVE, 1, "Goal.bmp", SPIF.None);