C# 绘制EMF图片

 private static bool DrawEmf(string filePath, int width, int heigth)
        {
            try
            {
                Bitmap bmp = new Bitmap(width, heigth);
                Graphics gs = Graphics.FromImage(bmp);
                Metafile mf = new Metafile(filePath, gs.GetHdc());

                Graphics g = Graphics.FromImage(mf);

                DrawDetails(g);

                g.Save();
                g.Dispose();
                mf.Dispose();

                return true;
            }
            catch
            {
                return false;
            }
        }

已知如上代码可以绘制EMF图片，但是必须要导出成文件，不知道如何可以保存到stream中？