Skift baggrund

Kode 

[DllImport("user32.dll", CharSet = CharSet.Auto)]

static extern int SystemParametersInfo(int uAction, int uParam, string lpvParam, int fuWinIni);

public MyForm(){
// Eventhandler btn1_Clicked
}

public void btn1_Clicked(object sender, EventArgs e){

SystemParametersInfo(20, 0, "Placering af billede\\billede.jpg", 0x01 | 0x02);

RegistryKey rkWallPaper = Registry.CurrentUser.OpenSubKey("Control Panel\\\\Desktop", true);

rkWallPaper.SetValue("WallpaperStyle", 2);

rkWallPaper.SetValue("TileWallpaper", 0);

rkWallPaper.Close();

}