如何将图形作为gif文件保存在硬盘上？

This is the code:

这是代码：

using (backbuffer = D3Ddev.GetBackBuffer(0, 0, BackBufferType.Mono))
            {
                using (g = backbuffer.GetGraphics())
                {
                    g.SmoothingMode = SmoothingMode.AntiAlias;

                    g.FillPie(myBrush, 256F - distanceFromCenterPixels, 255F - distanceFromCenterPixels,
                    distanceFromCenterPixels * 2F, distanceFromCenterPixels * 2F, angleF - 23F, 46F);
                    if (angleF < 360)
                        g.(@"c:\coneimages\" + angleF + ".gif");
                }
            }
using (backbuffer =