public class Papa
{
    public string param1 { get; set; }
    public Int32 param2 { get; set; }
}


public class Child1 : Papa
{
    public Int32 diablo(Int32 inVar)
    {
        return inVar * 10;
    }
}

public class Child2 : Papa
{
    public Int32 diablo(Int32 inVar)
    {
        return inVar * 2000;
    }
}

public void rr(byte inVar)
{
    switch (inVar)
    {
        case 1:
            {
                Child1 ddd = new Child1();
                break;
            }

        case 2:
            {
                Child2 ddd = new Child2();
                break;
            }
    }


    Console.WriteLine(ddd.diablo(inVar));
}

Public Class Papa
    Public Property param1 As String
    Public Property param2 As Int32
    Public Function diablo(inVar As Int32) As Int32
        Return 0
    End Function

End Class


Public Class Child1
    Inherits Papa
    Public Overloads Function diablo(inVar As Int32) As Int32
        Return inVar * 10
    End Function
End Class

Public Class Child2
    Inherits Papa
    Public Overloads Function diablo(inVar As Int32) As Int32
        Return inVar * 2000
    End Function
End Class

Public Class Papa
    Public Property param1 As String
    Public Property param2 As Int32
    Public Overridable Function Diablo(inVar As Int32) As Int32
        Return 555
    End Function

End Class


Public Class Child1
    Inherits Papa
    Public Overrides Function Diablo(inVar As Int32) As Int32
        Return inVar * 10
    End Function
End Class

Public Class Child2
    Inherits Papa
    Public Overrides Function diablo(inVar As Int32) As Int32
        Return inVar * 2000
    End Function
End Class
'******************************************************************
Module Module1

    Sub Main()
        Console.WriteLine(selection(1))
        Console.WriteLine(selection(2))
        Console.ReadLine()
    End Sub


'******************************************************************
    Public Function selection(inB As Byte) As Int32
        Dim myPapa As New Papa

        Select Case inB
            Case 1
                myPapa = New Child1
            Case 2
                myPapa = New Child2
        End Select

        Return myPapa.Diablo(inB)

    End Function
End Module