Checking for event handlers

[Darren]

Is there any way to check to see if there are any handlers registered
for a given event?

 

[Damien]

Is there any way to check to see if there are any handlers registered
for a given event?

Well, I have something in VB, hope this helps:

Public Class Blah
Public Shared Event InstanceAdded(ByVal sender as Object,ByVal e as
EventArgs)

Private Sub ClearCaches(ByVal OldState as CCOptions,ByVal NewState as
CCOptions)
If ((OldState Xor NewState) And CCOptions.CacheCollections) <> 0
Then
lstCache.Clear()
End If
If ((OldState Xor NewState) And CCOptions.CacheUpdateEvents) <> 0
Then
If Not InstanceAddedEvent is Nothing Then
For Each rb as System.Delegate in
InstanceAddedEvent.GetInvocationList()
RemoveHandler
InstanceAdded,DirectCast(rb,InstanceAddedEventHandler)
Next
End If
End If
End Sub
End Class

As you can see, VB creates a member called <Event Name>Event for each
event you declare. If someone has attached an event handler, then it
will be set to a <Event Name>EventHandler (which derives from
EventHandler). You can then query it's invocation list to get each
subscriber to the event.

HTH,

Damien

 

[S. Senthil Kumar]

Just check if the event instance is null, like
delegate void SomeDelegate(object sender, EventArgs e)

class Test
{
event SomeDelegate SomeEvent;

bool AreHandlersRegistered()
{
return SomeEvent != null;
}
}

Regards
Senthil