title: Catch InvalidOperationException with empty structure
body: <p>I am trying to catch the <code>InvalidOperationException</code> that can sometimes occur when declaring variables. The following code doesn't work however. Probably because I don't really know how you catch an exception. </p>
  
  <pre><code>public override void Download()
  {
      try
      {                                           
          var t = (ForumThread)Globals.Db.Thread.Get(_extIdForumThread, _idF);            
          try
          {
              throw new InvalidOperationException();
          }
          catch (InvalidOperationException exception)
          {
              return;
          }
          catch (Exception exception)
          {
              throw;
          }
      }
  }
  </code></pre>
  
  <p>Any help at all would be very appreciated.</p>