CODEWITHSUNDEEP
vb.net
Sorin GFS
Sorin GFS

Reputation: 519

vb.net how to reinitialize the base class from derived class after passing some parameters to it

I dont know if is posible, but I need to get recalculated properties of base class after passing parameter to it. Here is an example code:

Public Class BaseClass
    Public Property Initial As Integer
    Public Property Coeficient As Integer
    Public Property Multiplier As Integer = Coeficient * Initial

    Public Sub New()
        Me.New(0, 1) ' default initialization
    End Sub

    Public Sub New(ByVal Value1 As Integer, ByVal Value2 As Integer)
        Me.Initial = Value1
        Me.Coeficient = Value2
    End Sub

End Class

Public Class DerivedClass
    Inherits BaseClass

    Public Sub New()
        MyBase.New()
    End Sub

    Public Sub New(ByVal Value As Integer)
        MyBase.New(Value, 3) 'sets the coeficient to 3 and the Initial whatever is passed to it
    End Sub

End Class

Public Class TestClas

    Public Sub TestDerivedClass()

        Dim d As New DerivedClass(5)
        Dim result As Integer = d.Multiplier

        MsgBox(result) ' should be 15, but is not, because Multiplier need to be re-initialized somehow

    End Sub

End Class

I understand where the problem is, but what I need is to obtain kind of a dynamic base class to be inherited differently in multiple derived classes after passing different parameters to it.

Thank you in advance.

Upvotes: 0

Views: 81

Answers (2)

41686d6564
41686d6564

Reputation: 19641

The value of your Multiplier property doesn't get updated. If you want it to always return the multiplication of the other two values, you should convert it to a read-only property which will return the product.

Replace the following line:

Public Property Multiplier As Integer = Coeficient * Initial

with:

Public ReadOnly Property Multiplier() As Integer
    Get
        Return Coeficient * Initial
    End Get
End Property

Hope that helps.

Upvotes: 2

Morcilla de Arroz
Morcilla de Arroz

Reputation: 2182

Multiplier is a property, so it's such a Field of your class. When initialize, value is given.

You are expecting a "function behavior".

You can do many things, I don't know what you really need. Change Multiplier :

  • from property, to a Function As Integer
  • or to a Readonly property
  • or write the Get and Set Areas.

Simple Example:

Public ReadOnly Property Multiplier As Integer
  Get
    Return Coeficient * Initial
  End Get
End Property

This will give you the "automatic behavior" you are expecting

Upvotes: 0

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