Phillip Taylor wrote:
There IS a logical and application driven needs to one onto the other.
Take my exact requirements as stated in the original post: I have
objects or type "TableObject" (which signifies this the "Active
Record" approach to development). It makes perfect sense that you can
only implement Lockable objects on actual TableObjects. I mean you
can't lock something which isn't in the database. Hense if someone
implements Lockable, I want to force them to be sure that they've
implemented TableObject first.
Interface inheritance sounds like the way to go.
Interface ITableObject
Sub X()
Sub Y()
End Interface
Interface ILockableTableObject
Inherits ITableObject
Sub Z()
End Interface
Dim t1 as ITableObject
Dim t2 as ILockableTableObject
Sub HandleTable( t as Object )
If t Is ITableObject Then
With DirectCast( t, ITableObject )
. . .
End With
If t Is ILockableTableObject Then
With DirectCast( t, ILockableTableObject )
. . .
End With
End If
End If
End Sub
HTH,
Phill W.
>