Parameters

[rbulph]

How can I pass:

 

a) the AddressOf a procedure so as to use it with AddHandler; and

b) a Type so as to use it with TypeOf;

 

as parameters to a procedure?

[snarfblam]

(A)

Class Example
   'Declare Event
   Event SampleEvent As EventHandler
   
   Sub PassHandler()
       'Create Delegate
       Dim NewHandler As EventHandler = AddressOf Handler
       'Pass Delegate
       AttatchHandler(NewHandler)
   End Sub
   
   Sub AttatchHandler(Handler As EventHandler)
       'Attatch Delegate
       AddHandler SampleEvent, Handler
   End Sub
   
   'Use Delegate
   Sub Handler(Sender As Object, E As EventArgs)
       MessageBox.Show("Handled")
   End Sub
End Class

(B)

Class Example
   Sub PassType
       'GetType returns the runtime type of an object.
       Dim T As System.Type = Me.GetType()
       'The System.Type can be passed as a parameter.
       MessageBox.Show(IsMyType(T).ToString)
   End Sub
   
   Function IsMyType(System.Type T) As Boolean
       Dim MyType As System.Type = Me.GetType()

       If (MyType Is T) Or (T.IsSubclassOf(MyType)) Then
           'The above expression is the same as
           'If TypeOf(AnotherObject) Is TypeOf(Me).
           'We check if the two types are exactly the same (MyType Is T)
           'or if T is derived from MyType.
           Return True
       End If
       Return False
   End Function
End Class

I did not test the code, so I am not sure it is 100% correct, but you can certainly get the jist of it.

[rbulph]

Great, thanks.