C#图片裁切，生成新图片

        /// 图片裁剪，生成新图，保存在同一目录下,名字加_new，格式1.png  新图1_new.png
        /// </summary>
        /// <param name="picPath">要修改图片完整路径</param>
        /// <param name="x">修改起点x坐标</param>
        /// <param name="y">修改起点y坐标</param>
        /// <param name="width">新图宽度</param>
        /// <param name="height">新图高度</param>
        public static void cutPicture(String picPath, int x, int y, int width, int height)
        {
            //图片路径
            String oldPath = picPath;
            //新图片路径
            String newPath = System.IO.Path.GetExtension(oldPath);
            //计算新的文件名，在旧文件名后加_new
            newPath = oldPath.Substring(0, oldPath.Length - newPath.Length) + "_new" + newPath;
            //定义截取矩形
            System.Drawing.Rectangle cropArea = new System.Drawing.Rectangle(x, y, width, height);
            //要截取的区域大小
            //加载图片
            System.Drawing.Image img = System.Drawing.Image.FromStream(new System.IO.MemoryStream(System.IO.File.ReadAllBytes(oldPath)));
            //判断超出的位置否
            if ((img.Width < x + width) || img.Height < y + height)
            {
                MessageBox.Show("裁剪尺寸超出原有尺寸！");
                img.Dispose();
                return;
            }
            //定义Bitmap对象
            System.Drawing.Bitmap bmpImage = new System.Drawing.Bitmap(img);
            //进行裁剪
            System.Drawing.Bitmap bmpCrop = bmpImage.Clone(cropArea, bmpImage.PixelFormat);
            //保存成新文件
            bmpCrop.Save(newPath);
            //释放对象
            img.Dispose();
　　　　　　  bmpCrop.Dispose();
        }