using System.Reflection;
  ........
  private void HackCallEvent(object instance,
                             string eventName,EventArgs args)
  {
        MethodInfo mi = instance.GetType().GetMethod("On" eventName,BindingFlags.NonPublic|BindingFlags.Instance);
        if(mi != null)
          mi.Invoke(instance,new object[]{EventArgs.Empty});
  }
  
  sample.         HackCallEvent(button3,"Click",EventArgs.Empty);