wpf - RoutedEventHandler と RoutedEventArgs

Question

GetType(RoutedEventHandler) または GetType(RoutedEventArgs) でカスタム ルーティング イベントを登録する場合の違いは何ですか??

例1:

 Public Shared ReadOnly TextChangedEvent As RoutedEvent =   EventManager.RegisterRoutedEvent("TextChanged", _
               RoutingStrategy.Bubble, GetType(RoutedEventArgs), GetType(MyCustomTextBlock))

ex2 :

 Public Shared ReadOnly TextChangedEvent As RoutedEvent = EventManager.RegisterRoutedEvent("TextChanged", _
               RoutingStrategy.Bubble, GetType(RoutedEventHandler), GetType(MyCustomTextBlock))