title: Adding a directory to an existing .zip file
body: <p>First of all I would like to say that i've tried looking for the solution to this and I haven't found one where I don't have to unzip, add my folder and then zip again. I am not using any third party libraries. I would like to do this using system.io.compression if it's possible at all ... If not I would use dotnetzip as my last resort.</p>
  <p>TL;DR.
  I want to be able to add directories with files in them to an already created zip file. Is this possible using the <code>System.Io.Compression</code> library ?</p>
  <p><strong>EDIT</strong>:</p>
  <pre><code>using (FileStream zipToOpen = new FileStream(zipfile, FileMode.Open))
  {
      using (ZipArchive archive = new ZipArchive(zipToOpen, ZipArchiveMode.Update))
      {
          ZipArchiveEntry readmeEntry = archive.CreateEntry(&quot;testFolder/&quot;);
      }
  }
  </code></pre>
  <p>So, using this code I am able to create a folder inside but it will be without any files in it. My question now is do I have to run this code again to get every file from my source folder to this folder inside the zip or is there a better way?</p>