Is there a way to know in VB.NET if a handler has been registered for an event?

Question

In C# I can test for this...

public event EventHandler Trigger;
protected void OnTrigger(EventArgs e)
{
    if (Trigger != null)
        Trigger(this, e);
}
         


        

Answer 1

There's an interesting language "feature" in VB .NET. A member variable is created for events that exposes the delegate:

Public Event MyEvent As EventHandler
Public Sub Test()

    Dim test = MyEventEvent
    Dim invokers = test.GetInvocationList()

End Sub

You can actually get the invocation list this way.