超高兴，呵呵

      本以为图像分拆超难,没想到今天一下子就搞定了，高兴，五一不用加班了。今晚大吃一顿，庆祝庆祝，呵呵。

 

        /// <summary>
        /// 对给定的image进行图像分拆，截取指定位置的图片
        /// </summary>
        /// <param name="image">图像对象</param>
        /// <param name="x">x坐标</param>
        /// <param name="y">y坐标</param>
        /// <param name="w">宽度</param>
        /// <param name="h">高度</param>
        /// <returns>一个图像的内存流</returns>
        public static MemoryStream Crop(Image image, int x, int y, int w, int h)
        {
            //图形对象未实例话
            if (null == image) return null;

            //x坐标超出范围
            if (x < 0 || x > image.Width) return null;

            //y坐标超出范围
            if (y < 0 || y > image.Height) return null;

            //高度和宽带不能为负数
            if (w <= 0 || h <= 0) return null;

            //截取的图像超出范围
            if (image.Width < x + w || image.Height < y + h) return null;

            Bitmap bmp = new Bitmap(w, h, System.Drawing.Imaging.PixelFormat.Format24bppRgb);       //保存截取的图形

            Graphics graphics = Graphics.FromImage(bmp);                                            //从bmp创建图形操作对象

            graphics.DrawImage(image, new Rectangle(0, 0, w, h), x, y, w, h, GraphicsUnit.Pixel);   //在bmp中画出从image要截取的图像

            MemoryStream ms = new MemoryStream();
            bmp.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);

            graphics.Dispose();
            bmp.Dispose();

            return ms;

        }