public class GenerateThumbnail    {        private Image imageFrom;        /// <summary>        /// 源图的路径(含文件名及扩展名        /// </summary>        /// <param name="pathImageFrom">源图的路径(含文件名及扩展名</param>        public GenerateThumbnail(string pathImageFrom)        {            imageFrom = Image.FromFile(pathImageFrom);        }        /// <summary>        /// 生成缩略图 静态方法         /// </summary>        /// <param name="pathImageTo">生成的缩略图所保存的路径(含文件名及扩展名)注意：扩展名一定要与生成的缩略图格式相对应</param>        /// <param name="Percent">比例 例如 0.8...</param>        public void GenThumbnail(string pathImageTo, double Percent)        {            GenThumbnail(pathImageTo, Convert.ToInt32(imageFrom.Width * Percent), Convert.ToInt32(imageFrom.Height * Percent));        }        /**/        /// <summary>         ///  生成缩略图 静态方法            /// </summary>         /// <param name="pathImageTo"> 生成的缩略图所保存的路径(含文件名及扩展名)         ///                            注意：扩展名一定要与生成的缩略图格式相对应 </param>         /// <param name="width"> 欲生成的缩略图 "画布" 的宽度(像素值) </param>         /// <param name="height"> 欲生成的缩略图 "画布" 的高度(像素值) </param>         public void GenThumbnail(string pathImageTo, int width, int height)        {            Bitmap bmp = new Bitmap(width, height);            Graphics g = Graphics.FromImage(bmp);            g.InterpolationMode = InterpolationMode.HighQualityBicubic;            g.SmoothingMode = SmoothingMode.HighQuality;            g.DrawImage(imageFrom, new Rectangle(0, 0, width, height), new Rectangle(0, 0, imageFrom.Width, imageFrom.Height), GraphicsUnit.Pixel);            try            {                if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Jpeg))                    bmp.Save(pathImageTo, ImageFormat.Jpeg);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Png))                    bmp.Save(pathImageTo, ImageFormat.Png);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Gif))                    bmp.Save(pathImageTo, ImageFormat.Gif);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Icon))                    bmp.Save(pathImageTo, ImageFormat.Icon);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Tiff))                    bmp.Save(pathImageTo, ImageFormat.Tiff);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Wmf))                    bmp.Save(pathImageTo, ImageFormat.Wmf);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Bmp))                    bmp.Save(pathImageTo, ImageFormat.Bmp);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Emf))                    bmp.Save(pathImageTo, ImageFormat.Emf);                else if (imageFrom.RawFormat.Equals(System.Drawing.Imaging.ImageFormat.Exif))                    bmp.Save(pathImageTo, ImageFormat.Exif);                else                    throw new Exception("无此类型图片");            }            finally            {                //显示释放资源                 imageFrom.Dispose();                bmp.Dispose();                g.Dispose();            }        }    }