title: c# wpf Datetime changed (New day has come) event
body: <p>Hello guys I trying to do something like this to create event which starts to do something when new date has came like it was 2014/01/01 and it is  2014/01/02 and then do some stuff :</p>
  
  <pre><code>private void Datetime.now_changed(days)(object sender, RoutedEventArgs e)
      {
             do some stuff;
      }
  </code></pre>
  
  <p>What should I do?</p>