Re: Child objects inheriting property values

Thanks Peter, I think I will go with this.  Although my delimiter will be a
string, and thus a reference type, which had previously introduced doubts in
my musings, as I was paranoid about the Record delimiter being changed on
the parent, introducing possibly unexpected side effects in the child.
However,, I think it will suffice to explicitly set the Column delimiter to
a clone of the parent, if I want an immutable delimiter for some odd reason.

> -----Original Message-----
> From: Discussion of development on the .NET platform using any managed
> language [mailto:[email protected]] On Behalf Of Peter
> Obiefuna
> Sent: 22 November 2007 05:40 AM
> To: [email protected]
> Subject: Re: [DOTNET-CLR] Child objects inheriting property values
>
> Using inheritance is semantically wrong since a Column 'IS A' record is
> not
> correct. Moreover, assigning field values of a base class to its
> subclass in
> a constructor feels awkward. A good compiler should disallow it.
> Again, the class order in your question appears reversed to me (I
> expect a
> column collection to exist before a record does) but I'll just answer
> your
> question narrowly. Here's my solution to that problem.
> =======================================
>
> class Column{
>
>     private char delimiter;
>     public Column(){
>         // first, set parent record;
>         // then ...
>         this.delimiter = ParentRecord.Delimiter;
>     }
>     public Record ParentRecord { get; set; }
>     public char Delimiter { get; set; }
> }
>
> class Record{
>     private char delimiter = '^';
>     public Record(){
>
>     }
>     private Column[] columns;
>     public char Delimiter {get; set;}
>
> }
>
> --------------------------------------------------
> From: "Adrian Martin" <[email protected]>
> Sent: Tuesday, November 20, 2007 6:28 AM
> To: <[email protected]>
> Subject: Re: [DOTNET-CLR] Child objects inheriting property values
>
> >        class Column : Record
> >        {
> >                public Column()
> >                {
> >                        this.Delimeter = base.Delimeter;
> >                }
> >        }
> >
> >
> >
> >
> >
> >
> >
> > -----Original Message-----
> > From: Discussion of development on the .NET platform using any
> managed
> > language [mailto:[email protected]] On Behalf Of Brady
> > Kelly
> > Sent: 20-November-2007 10:10
> > To: [email protected]
> > Subject: Child objects inheriting property values
> >
> > I have a hierarchy of objects that share some attributes, e.g. both
> my
> > parent Record and Column objects have a columnDelimiter property.  I
> > want
> > this property on the Column object to default to the same property on
> > the
> > Record object, until specified on the Column object.  What is the
> best
> > way
> > to go about this?  I could give each Column a reference to the Record
> it
> > belongs to, but this seems not quite right to me.  My other option is
> to
> > have the Record act as a ColumnFactory, setting the columnDelimiter
> > value on
> > each Column it creates, until a set accessor on Column optionally
> > overrides
> > that default value.
> >
> >
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