Работа с файлами

var dialog = new SaveFileDialog() { Filter = "*.jpeg; | *.jpeg;" };
if (dialog.ShowDialog().GetValueOrDefault())
{
    BtnUplode.Visibility = Visibility.Collapsed;

    var render = new RenderTargetBitmap((int)GridPng.ActualWidth, (int)GridPng.ActualHeight, 96, 96, PixelFormats.Pbgra32);
    render.Render(GridPng);
    var encoder = new JpegBitmapEncoder();
    encoder.Frames.Add(BitmapFrame.Create(render));

    var file = File.Create(dialog.FileName);
    encoder.Save(file);
    file.Close();
}
BtnUplode.Visibility = Visibility.Visible;
      

var dialog = new PrintDialog();
if (dialog.ShowDialog().GetValueOrDefault())
{
    BtnUplode.Visibility = Visibility.Collapsed;

    dialog.PrintVisual(GridPng, "test");
}
BtnUplode.Visibility = Visibility.Visible;