将图片保存到硬盘

Question

我想调整大小和安全的图片我已经做了一些研究，并试图让sommething工作。几乎所有的东西都可以工作，但是保存给了我一个无效的参数例外。 这是我有：

 private void ResizeImage(Image image) 
    { 
     int maxWidth = 100; 
     int maxHeight = 100; 
     int imageWidth = image.Size.Width; 
     int imageHeight = image.Size.Height; 

     double maxRatio = (double)maxWidth/(double)maxHeight; 
     double picRatio = (double)imageWidth/(double)imageHeight; 

     Image newImage = null; 
     if (maxRatio > picRatio && imageWidth > maxWidth) 
     { 
      newImage = new Bitmap(image, new System.Drawing.Size(Convert.ToInt32(maxWidth/picRatio), maxHeight));    
     } 
     else if (maxRatio < picRatio && imageHeight > maxHeight) 
     { 
      newImage = new Bitmap(image, new System.Drawing.Size(maxWidth, Convert.ToInt32(maxHeight/picRatio)));   
     } 

     // Encoder parameter for image quality 
     EncoderParameter qualityParam = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality,1); 

     // Jpeg image codec 
     ImageCodecInfo jpegCodec = this.getEncoderInfo("image/jpeg"); 

     if(jpegCodec != null){ 
      EncoderParameters encoderParams = new EncoderParameters(1); 
      encoderParams.Param[0] = qualityParam; 
      newImage.Save(@".\temp\pdf\photos\test.jpg",jpegCodec,encoderParams); 
     } 
    } 

    private ImageCodecInfo getEncoderInfo(string mimeType) 
    { 
     // Get image codecs for all image formats 
     ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders(); 

     // Find the correct image codec 
     for (int i = 0; i < codecs.Length; i++) 
     { 
      if (codecs[i].MimeType == mimeType) 
      { 
       return codecs[i]; 
      } 
     } 
     return null; 
    } 

但是当我尝试运行它，它给了我在newImage.save无效参数异常（）

Answer 1

据MSDN，编码质量参数应为64位（长）值。改变这一行：

var qualityParam = new EncoderParameter(Encoder.Quality, 1); 

到

var qualityParam = new EncoderParameter(Encoder.Quality, 1L);