/ / 缩小图片 / / 源图文件名(绝对路径) / 目标宽度（允许的最大宽度） / 新图片质量（1-100） public void ResizePic(string strPath, int newWidth, int quality) Bitmap bmOld, bmNew; try /读取原图片 bmOld = new Bitmap(strPath); /为了解决Bitmap不释放资源问题，先不同的名称保存图片，缩放完后把临时文件删除 string tempPath = strPath.Replace(., _temp.); int oldWidth = bmOld.Width; int oldHeight = bmOld.Height; int newHeight = (int)(double)newWidth / oldWidth * oldHeight); if (oldWidth newWidth) newWidth = oldWidth; newHeight = oldHeight; /建立新Bitmap用于缩放图片 bmNew = new Bitmap(bmOld, newWidth, newHeight); /保存缩放后的图片 bmNew.Save(tempPath); bmOld.Dispose(); bmNew.Dispose(); /获取图片Encoder信息 ImageCodecInfo codecs = ImageCodecInfo.GetImageEncoders(); ImageCodecInfo ici = null; foreach (ImageCodecInfo codec in codecs) if (codec.MimeType = image/jpeg) ici = codec; EncoderParameters ep = new EncoderParameters(); /给定的参数quality ep.Param0 = new EncoderParameter(Encoder.Quality, (long)quality); /从临时文件中读取图片 Image img = Image.FromFile(tempPath); /以给定的参数保存图片 img.Save(strPath, ici, ep); img.Dispose(); /最后删除临时图片 File.Delete(tempPath); catch (Exception ex) new Database().SysLog(ex, PicStore.ResizePic( + strPath + , + newWidth + , + quality + ,); finally bmOld = null; bmNew = null;