title: Observable: Anonymous function converted to a void returning delegate cannot return a value C#
body: <p>Im trying to get the content of multiple websites by using Observable and creating multiple subscriptions. I managed to get the contents but can't return the string from this method. What type of return is necessary for this Anonymous function?</p>
  
  <pre><code>public static void call(string url)
      {
          var query =
          from r in Observable.Using(
          () =&gt; new WebClient(),
          wc =&gt; Observable.Start(() =&gt; wc.DownloadString($"{url}")))
          select r;
  
          IDisposable subscription =
              query
                  .Subscribe(r =&gt;
                  {
                      /*return r ? */
                  });
      }
  </code></pre>
  
  <p>I first tried with <code>public static string call(string url)</code>
  and also <code>public static Func&lt;string&gt;(string url)</code> but still not getting this right.</p>