1 public static class ImageCompress 2  { 3 /// <summary> 4 /// 图片压缩 5 /// </summary> 6 /// <param name="imagePath">图片文件路径</param> 7 /// <param name="targetFolder">保存文件夹</param> 8 /// <param name="quality">压缩质量</param> 9 /// <param name="fileSuffix">压缩后的文件名后缀（防止直接覆盖原文件）</param>10 public static void CompressionImage(string imagePath, string targetFolder, long quality = 100, string fileSuffix = "compress")11  {12 if (!File.Exists(imagePath))13  {14 throw new FileNotFoundException();15  }16 if (!Directory.Exists(targetFolder))17  {18  Directory.CreateDirectory(targetFolder);19  }20 var fileInfo = new FileInfo(imagePath);21 var fileName = fileInfo.Name.Replace(fileInfo.Extension, "");22 var fileFullName = Path.Combine($"{targetFolder}", $"{fileName}_{fileSuffix}{fileInfo.Extension}");23 24 var imageByte = CompressionImage(imagePath, quality);25 var ms = new MemoryStream(imageByte);26 var image = Image.FromStream(ms);27  image.Save(fileFullName);28  ms.Close();29  ms.Dispose();30  image.Dispose();31  }32 private static byte[] CompressionImage(string imagePath, long quality)33  {34 using (var fileStream = new FileStream(imagePath, FileMode.Open))35  {36 using (var img =Image.FromStream(fileStream))37  {38 using (var bitmap = new Bitmap(img))39  {40 var codecInfo = GetEncoder(img.RawFormat);41 var myEncoder = Encoder.Quality;42 var myEncoderParameters = new EncoderParameters(1);43 var myEncoderParameter = new EncoderParameter(myEncoder, quality);44 myEncoderParameters.Param[0] = myEncoderParameter;45 using (var ms = new MemoryStream())46  {47  bitmap.Save(ms, codecInfo, myEncoderParameters);48  myEncoderParameters.Dispose();49  myEncoderParameter.Dispose();50 return ms.ToArray();51  }52  }53  }54  }55  }56 57 private static ImageCodecInfo GetEncoder(ImageFormat format)58  {59 var codecs = ImageCodecInfo.GetImageDecoders();60 return codecs.FirstOrDefault(codec => codec.FormatID == format.Guid);61  }62 }

 private void Button_Click(object sender, RoutedEventArgs e) { var fileDialog = new OpenFileDialog(); var fileSelect = ""; if (fileDialog.ShowDialog(this)==true) { fileSelect = fileDialog.FileName; } if(string.IsNullOrWhiteSpace(fileSelect)) return; ImageCompress.CompressionImage(fileSelect,@"d:\",50); }