MustInherit Class with parameters in the constructor

by:Francisco Amaro


Hi all,

Have question about inheriting a class that has parameters in the
constructor such as :

Public MustInherit Class MyParentClass

Public mystring As String

Public Sub New(ByVal paramstring As String)
mystring = paramstring
End Sub

End Class

When I create the subclass :

Public Class MyChildClass <-- VS warns of a Problem here
Inherits MyParentClass

Public Sub ShowString()
MsgBox(mystring)
End Sub

End Class
VS.NET is complaining I need to declare a "sub new" in the child class
because "The base class doesn't have an accessible 'Sub new' that can be
called without arguments."

I don't understand why this should be necessary, I have no intentions of
creating and instance of this child class without the proper arguments in
New, why should a redefinition of the constructor be required?

Is this a special case for the constructor or am I missing something in how
inheritance works in .net ?

Thanks for any clarification provided,
Francisco