question about inheritance and Imports statement

15 Nov 2006 4:08 PM

BillE

Does a subclass have to import namespaces which were already imported by the
superclass?

I have a base class which imports the System.Data.SQLClient namespace to use
the dataset member.

When I inherit this base class, the subclass must also import the
System.Data.SQLClient namespace to use its members.

I thought that a subclass would not have to re-import namespaces which were
already imported by the superclass.

Do I understand correctly, or am I doing something wrong?

Thanks
Bill

15 Nov 2006 4:40 PM

Robinson

If you go to your project properties -> References, you can import the
reference for the entire project, rather than doing it on a file by file
basis.

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"BillE" <bel***@datamti.com> wrote in message
news:eFPeOBNCHHA.2328@TK2MSFTNGP02.phx.gbl...
> Does a subclass have to import namespaces which were already imported by
> the superclass?
>
> I have a base class which imports the System.Data.SQLClient namespace to
> use the dataset member.
>
> When I inherit this base class, the subclass must also import the
> System.Data.SQLClient namespace to use its members.
>
> I thought that a subclass would not have to re-import namespaces which
> were already imported by the superclass.
>
> Do I understand correctly, or am I doing something wrong?
>
> Thanks
> Bill
>
>

15 Nov 2006 5:16 PM

Chris Dunaway

Robinson wrote:

> If you go to your project properties -> References, you can import the
> reference for the entire project, rather than doing it on a file by file
> basis.

You cannot use the Imports statement without first adding a reference
to the corresponding assembly. In other words you cannot add a
reference on a file by file basis. References are *always* added a
project level.

That said, the Imports statement has nothing to do with inheritance.
It is simply a means of easing the amount of typing a developer has to
do. Internally, the compiler works with the fully qualified type name.

Show quoteHide quote

>
> "BillE" <bel***@datamti.com> wrote in message
> news:eFPeOBNCHHA.2328@TK2MSFTNGP02.phx.gbl...
> > Does a subclass have to import namespaces which were already imported by
> > the superclass?
> >
> > I have a base class which imports the System.Data.SQLClient namespace to
> > use the dataset member.
> >
> > When I inherit this base class, the subclass must also import the
> > System.Data.SQLClient namespace to use its members.
> >
> > I thought that a subclass would not have to re-import namespaces which
> > were already imported by the superclass.
> >
> > Do I understand correctly, or am I doing something wrong?
> >
> > Thanks
> > Bill
> >
> >

15 Nov 2006 5:26 PM

Robinson

> You cannot use the Imports statement without first adding a reference
> to the corresponding assembly. In other words you cannot add a
> reference on a file by file basis. References are *always* added a
> project level.
>
> That said, the Imports statement has nothing to do with inheritance.
> It is simply a means of easing the amount of typing a developer has to
> do. Internally, the compiler works with the fully qualified type name.

Yes, but you can add a reference to the assembly AND import the namespace in
project settings.

15 Nov 2006 6:34 PM

Chris Dunaway

Robinson wrote:

> > You cannot use the Imports statement without first adding a reference
> > to the corresponding assembly. In other words you cannot add a
> > reference on a file by file basis. References are *always* added a
> > project level.
> >
> > That said, the Imports statement has nothing to do with inheritance.
> > It is simply a means of easing the amount of typing a developer has to
> > do. Internally, the compiler works with the fully qualified type name.
>
> Yes, but you can add a reference to the assembly AND import the namespace in
> project settings.

Ah yes! Your first post said "References" so I was thinking about
adding a reference to another assembly, when you were actually
referring to the References section in the properties page and the
Imported Namespaces section on that.

I primarily use C# which does not have this feature, hence my
puzzlement.