title: Compare files to files inside a Zip archive
body: <p>I have a zip file which I extract to a folder. I then need to open the files and perform various functions but the files are not modified or saved at all.</p>
  <p>I use Dotnetzip to extract the files from the archive before the files are opened and viewed etc.</p>
  <p>Is there a way to compare the files, which was extracted, to the files still inside the zip file without extracting those files again? The zip files I have is quite large. Some of them several 100 Mb's so don't want to wait for another extraction process again.
  Thanks!</p>