Type Mismatch
in [VB.NET]
|
From: Dave T on 23 Feb 2010 11:44 I have a type *Address* and a type *ResidentialAddress* which inherits Address. When I try to execute SOMECLASS.ResAddr = OTHERCLASS.Addr I get the inevitable type mis-match error "unable to cast type ObjectModel.Address to Type ObjectModel.ResidentialAddress" I was thinking that since ResidentialAddress inherits Address, there must be some way to do this assignment
From: Cor Ligthert[MVP] on 23 Feb 2010 12:33 Hello Dave, Yea but commonly your properties have the same names if you don't cast them using an interface. I would not use a class name Address, that is to ambiguous (to often used) in Net. Cor "Dave T" <DaveT(a)discussions.microsoft.com> wrote in message news:A8A33D7C-C3B9-4101-83A9-68190EE1BDB5(a)microsoft.com... > I have a type *Address* and a type *ResidentialAddress* which inherits > Address. When I try to execute SOMECLASS.ResAddr = OTHERCLASS.Addr I get > the > inevitable type mis-match error "unable to cast type ObjectModel.Address > to > Type ObjectModel.ResidentialAddress" I was thinking that since > ResidentialAddress inherits Address, there must be some way to do this > assignment
From: Armin Zingler on 23 Feb 2010 12:24 Dave T schrieb: > I have a type *Address* and a type *ResidentialAddress* which inherits > Address. When I try to execute SOMECLASS.ResAddr = OTHERCLASS.Addr I get the > inevitable type mis-match error "unable to cast type ObjectModel.Address to > Type ObjectModel.ResidentialAddress" I was thinking that since > ResidentialAddress inherits Address, there must be some way to do this > assignment You're trying to assign an Address to a ResidentialAddress. Not every Address is a ResidentialAddress. OTHERCLASS.Addr can also be a WhateverAddress which is not a ResidentialAddress. Or it can just be an Address. Therefore it fails. If you know that OTHERCLASS.Addr _always_ returns a ResidentialAddress, you can type cast the reference SOMECLASS.ResAddr = DirectCast(OTHERCLASS.Addr, ResidentialAddress) Or, if possible, the type of OTHERCLASS.Addr can be changed to ResidentialAddress. -- Armin
|
Pages: 1 Prev: GetTickCount() confusion in VB Next: Use one routine for several events |