有种做法是合并图片        /// <summary>
        /// 合并图片
        /// </summary>
        /// <param name="maps">图片集</param>
        /// <param name="RepeatDirection">合并方向</param>
        /// <returns></returns>
        public static Bitmap MergerImg(Bitmap[] maps, System.Web.UI.WebControls.RepeatDirection RepeatDirection)
        {
            if (maps.Length == 0)
                throw new Exception("图片数不能够为0");            int _width = 0;
            int _height = 0;
            for (int i = 0; i < maps.Length; i++)
            {
                if (RepeatDirection == System.Web.UI.WebControls.RepeatDirection.Horizontal)
                {
                    _width += maps[i].Width;
                    if (maps[i].Height > _height)
                    {
                        _height = maps[i].Height;
                    }
                }
                else
                {
                    _height += maps[i].Height;
                    if (maps[i].Width > _width)
                    {
                        _width = maps[i].Width;
                    }
                }
            }
            //创建要显示的图片对象,根据参数的个数设置宽度
            Bitmap backgroudImg = new Bitmap(_width, _height);
            Graphics g = Graphics.FromImage(backgroudImg);            //清除画布,背景设置为白色
            int len = maps.Length;
            g.Clear(System.Drawing.Color.White);
            int x = 0;
            for (int j = 0; j < len; j++)
            {
                if (RepeatDirection == System.Web.UI.WebControls.RepeatDirection.Horizontal)
                {
                    g.DrawImage(maps[j], x, 0, maps[j].Width, maps[j].Height);
                    x = x + maps[j].Width;
                }
                else
                {
                    g.DrawImage(maps[j], 0, x, maps[j].Width, maps[j].Height);
                    x = x + maps[j].Height;
                }
            }
            g.Dispose();
            return backgroudImg;
        }