WPF

namespace WpfApplication5
{
    /// <summary>
    /// Interaction logic for App.xaml
    /// </summary>
    public partial class App : System.Windows.Application
    {
        void OnStartup(Object sender, StartupEventArgs e)
        {

            //creates window on primary screen
            Window1 primaryWindow = new Window1();
            primaryWindow.WindowStartupLocation = WindowStartupLocation.Manual;
            System.Drawing.Rectangle location = System.Windows.Forms.Screen.PrimaryScreen.Bounds;
            primaryWindow.WindowState = WindowState.Maximized;
            string Path = Environment.CurrentDirectory + "\\images";

            //creates window on other screens
            foreach (System.Windows.Forms.Screen screen in System.Windows.Forms.Screen.AllScreens)
            {
                if (screen == System.Windows.Forms.Screen.PrimaryScreen)
                {
                    Window1 window = new Window1();
                    window.Photos = (PhotoCollection)(this.Resources["Photos"] as ObjectDataProvider).Data;
                    window.Photos.Path = Environment.CurrentDirectory + "\\Images";

                    for (int i = 0; i < window.Photos.Count; ++i)
                    {  
                        window.WindowStartupLocation = WindowStartupLocation.Manual;
                        location = screen.Bounds;
                        //covers entire monitor
                        window.Left = location.X - 7;
                        window.Top = location.Y - 7;
                        window.Width = location.Width + 14;
                        window.Height = location.Height + 14;
                        
            
                        if (i > 0)
                            System.Threading.Thread.Sleep(40);
                        window.ScreenSaver(window.Photos[i].Source);

                        window.Show();
                        
                    }
                }
            }

        }

    }
}
    public partial class Window1 : System.Windows.Window
    {
        public PhotoCollection Photos;
        public Window1()
        {
            InitializeComponent();
        }

        void OnLoaded(object sender, EventArgs e)
        {
            //Initialize background color with BackgroundColor application setting
            TypeConverter colorTypeConverter = TypeDescriptor.GetConverter(typeof(Color));
            Background = new SolidColorBrush((Color)colorTypeConverter.ConvertFrom(Properties.Settings.Default.BackgroundColor));
        }
       
       
        public void ScreenSaver(string imagepath)
        {
            StackPanel mainPanel = new StackPanel();

            Window1 window = new Window1();
            ImageBrush picturebrush = new ImageBrush();
            picturebrush.ImageSource =
                new BitmapImage(
                    new Uri(imagepath, UriKind.Relative)
                );

            Canvas myCanvas = new Canvas();
            System.Drawing.Rectangle location = System.Windows.Forms.Screen.PrimaryScreen.Bounds;
   
            //covers entire monitor
            window.Left = location.X - 7;
            window.Top = location.Y - 7;
            myCanvas.Width = location.Width + 14;
            myCanvas.Height = location.Height + 14;
            //myCanvas.Width = 300;
            //myCanvas.Height = 200;
            myCanvas.Background = picturebrush;
           
            mainPanel.Children.Add(myCanvas);
            this.Content = mainPanel;