VB.Net Tutorial/Class Module/NotOverridable

NotOverridable

Public Class Base
    Public Overridable Function greet() As String
        Return "Greeting from the Base!"
    End Function
End Class
Public Class Derived1
    Inherits Base
    Public Overrides Function greet() As String
        Return "middle greet"
    End Function
End Class
Public Class Derived2
    Inherits Derived1
    Public NotOverridable Overrides Function greet() As String
    End Function
End Class
Public Class bottom
    Inherits Derived2
End Class