title: How to get the duration of mp3 track?
body: <p>I would like to ask how can I get length of my audio file in app. </p>
  
  <p>I'm loading track like this </p>
  
  <pre><code>var installFolder = Windows.ApplicationModel.Package.Current.InstalledLocation;
  
  var resourcesFolder = await installFolder.GetFolderAsync("Resources");
  var mp3FilesFolder = await resourcesFolder.GetFolderAsync("mp3Files");
  
  var audioFile = await mp3FilesFolder.GetFileAsync("sound.mp3");
  var stream = await audioFile.OpenAsync(Windows.Storage.FileAccessMode.Read);
  
  mediaplayer.SetSource(stream, audioFile.ContentType);
  mediaplayer.Play();
  </code></pre>
  
  <p>but I don't know how to get the duration of track?</p>