Bitmap bmp = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height, PixelFormat.Format32bppArgb);
Graphics gp = Graphics.FromImage(bmp);
gp.CopyFromScreen(0, 0, 0, 0, new Size(bmp.Width, bmp.Height));
BinaryFormatter bFormat = new BinaryFormatter();
bFormat.Serialize(ns, bmp);
gp.Dispose();
bmp.Dispose();