VB.netのイベントの明示的な追加/削除

Question

eventがサブスクライブ/サブスクライブされていない場合、C＃では明示的にadd/removeコードを定義できます。

これはVB.netで可能ですか？

Answer 1

Imports System.Runtime.CompilerServices 
... 
    Private propchanged As PropertyChangedEventHandler 

    Public Custom Event PropertyChanged As PropertyChangedEventHandler 

     <MethodImpl(MethodImplOptions.Synchronized)> _ 
     AddHandler(ByVal value As PropertyChangedEventHandler) 
      propchanged = DirectCast([Delegate].Combine(propchanged, value), PropertyChangedEventHandler) 
     End AddHandler 

     <MethodImpl(MethodImplOptions.Synchronized)> _ 
     RemoveHandler(ByVal value As PropertyChangedEventHandler) 
      propchanged = DirectCast([Delegate].Remove(propchanged, value), PropertyChangedEventHandler) 
     End RemoveHandler 

     RaiseEvent(ByVal sender As Object, ByVal e As System.ComponentModel.PropertyChangedEventArgs) 
      Dim handler = propchanged 
      If handler IsNot Nothing Then handler(sender, e) 
     End RaiseEvent 
    End Event 

Answer 2

定義されたカスタムイベントを使用して行うことができるように見えます。here。

' Define the MouseDown event property. 
    Public Custom Event MouseDown As MouseEventHandler 
     ' Add the input delegate to the collection. 
     AddHandler(Value As MouseEventHandler) 
      listEventDelegates.AddHandler(mouseDownEventKey, Value) 
     End AddHandler 
     ' Remove the input delegate from the collection. 
     RemoveHandler(Value As MouseEventHandler) 
      listEventDelegates.RemoveHandler(mouseDownEventKey, Value) 
     End RemoveHandler 
     ' Raise the event with the delegate specified by mouseDownEventKey 
     RaiseEvent(sender As Object, e As MouseEventArgs) 
      Dim mouseEventDelegate As MouseEventHandler = _ 
       listEventDelegates(mouseDownEventKey) 
      mouseEventDelegate(sender, e) 
     End RaiseEvent 
    End Event