Re: User Controls (Active X) - Da Process

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"Ralph" <nt_consulting64@xxxxxxxxx> wrote

I get annoyed everytime I hear the expression "VB cannot do *real*
inheritance".
<snipped for brievity>

I'd agree with that sentiment. VB can't do 'real' inheritance.

For me inheritance includes the implementation as well as the interface.

VB's 'interface inheritance' is more like interface duplication, from
which you get polymorphism. When a VB class implements an interface,
it has to implement all the members of that interface, even where the
code is a duplication of whats in the base class.

Even if the class delegates to an internally held base class, its still a
duplication in that the world calls on an inheirited member, and the
class in turn calls on the base class member. A process that is
duplicated for every level of inheiritance.

Another thing which doesn't sit right with me, if B inheirits A,
and C inheirits B, then the C object should be able to called
like an object of type A. Something VB's 'interface inheiritance'
doesn't do. In other words, it doesn't go multi-levels, like 'true'
inheiritance should....

<insert>2 cents</insert>
LFS



.

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