Static variables and inheritance

"grmAbay" <grmAbay@hotmail.com> wrote:
>Hello,
>
>I ran into a problem I didn't realize before:
>
>- I've got a a Parent class declaring a static variable. The parent class
>also provides a method to return that static variable.
>- I've got two child classes (ChildA and ChildB) inheriting from the Parent
>class. these also initialize the static variable in the constructor.
>Look at the code below.
>public abstract class Parent {
> protected static string message;
> public Parent () { }
> public string GetMessage() {return message;}
>}

>
>class ChildA : Parent {
> public ChildA () {message = "Hello from ChildA";}
>}
>
>class ChildB : Parent {
> public ChildB () {message = "Hello from ChildB";}
>}
>
>When I run :
> ChildA testA = new ChildA();
> ChildB testB = new ChildB();
> Console.Write(" {0} - {1}, testA.GetMessage(), testB.GetMessage());
> It returns "Hello from ClassB - Hello from ClassB"
>
>My goal however was to provide an abstract Parent class. Every child class
>would initialize its own static variable, and would use the Parent method
>'GetMessage' to return it. My intuitive way of solving this would be to
>declare the static variable as abstract. However, this isn't allowed in
C#.
>
>I can't find an elegant way to solve this problem without having to declare
>the static variable and implement the 'GetMessage()' method in every
>subclass.
>
>Any clues?
>
>
I agree with Dave. You don't want message to be static. The whole point
of a static is to have a single instance shared by all instantiations of
the class, including derived (child) objects.