1.FileStream fs = new FileStream(path, FileMode.Create);
   fs.Write(ImageBuff, 0, ImageBuff.Length);
   fs.Close();

注释：ImageBuff 图片流，byte[]类型。path保存文件的路径

2. MemoryStream ms = new MemoryStream(ImageBuff);
    Image img = Image.FromStream(ms);
    img.Save(path);

流文件保存到本地的两种方法