title: Postsharp AOP MethodInterception Aspect with async
body: <p>In my winform programme I use Postsharp interceptor class on each control event to avoid try/catch block repetition.</p>
  
  <p>The custom postsharp method:</p>
  
  <pre><code>[Serializable]
  public class OnErrorShowMessageBox : MethodInterceptionAspect
  {
      public override void OnInvoke(MethodInterceptionArgs args)
      {
          try
          {               
              args.Proceed();
          }
          catch (Exception ex)
          {
              MessageBox.Show(ex.Message, "Erreur", MessageBoxButtons.OK, MessageBoxIcon.Error);
              args.ReturnValue = null;
          }
      }
  }
  </code></pre>
  
  <p>Usage this the attributs:</p>
  
  <pre><code>    [OnErrorShowMessageBox]
      private void txtComments_TextChanged(object sender, EventArgs e)
      {
         //blabla
      }
  </code></pre>
  
  <p>This works like a charm BUT know I would like to use async on the event. So txtComments_textChanged become :</p>
  
  <pre><code>    [OnErrorShowMessageBox]
      private async void txtComments_TextChanged(object sender, EventArgs e)
      {
          await //blabla
      }
  </code></pre>
  
  <p>And here comes the problem. Try/catch bloc in the interceptor method don't catch anything when is async...
  How can I do ?
  thanks</p>