public void EstimateResponseInfo()
{
IEncoder guessedEncoder = null;
//Only use an encoder to determine extension/mime-type when it's an image extension or when we've set process = always.
if (ProcessingIndicated)
{
guessedEncoder = conf.GetImageBuilder().EncoderProvider.GetEncoder(new ResizeSettings(this.RewrittenInstructions), this.RewrittenVirtualPath);
if (guessedEncoder == null)
{
throw new ImageProcessingException("Image Resizer: No image encoder was found for the request.");
}
}
//Determine the file extension for the caching system to use if we aren't processing the image
//Use the existing one if is an image extension. If not, use "unknown".
// We don't want to suggest writing .exe or .aspx files to the cache!
string fallbackExtension = PathUtils.GetFullExtension(RewrittenVirtualPath).TrimStart('.');
if (!conf.IsAcceptedImageType(RewrittenVirtualPath))
{
fallbackExtension = "unknown";
}
//Determine the mime-type if we aren't processing the image.
string fallbackContentType = "application/octet-stream";
//Support JPEG, PNG, GIF, BMP, TIFF mime-types. Otherwise use "application/octet-stream".
//We can't set it to null - it will default to text/html
System.Drawing.Imaging.ImageFormat recognizedExtension = DefaultEncoder.GetImageFormatFromExtension(fallbackExtension);
if (recognizedExtension != null)
{
fallbackContentType = DefaultEncoder.GetContentTypeFromImageFormat(recognizedExtension);
}
EstimatedContentType = ProcessingIndicated ? guessedEncoder.MimeType : fallbackContentType;
EstimatedFileExtension = ProcessingIndicated ? guessedEncoder.Extension : fallbackExtension;
Performance.GlobalPerf.Singleton.IncrementCounter("module_response_ext_" + EstimatedFileExtension);
}
