On Fri, 18 Apr 2008 19:22:57 -0700, Shawn Wildermuth <[EMAIL PROTECTED]> wrote:
>I would say that using inheritance in LINQ to SQL isn't a good approach. >Entity Framework is better than most but you might consider either using >LINQ for SQL or EF (or nHibernate) as your data access layer and using the >dal as the 'fillers' for real business objects. > >Thanks, you may be right, I'm really trying to get my head around using the vanilla microsoft tools...and this is an example. > >Shawn Wildermuth >http://adoguy.com >http://wildermuthconsulting.com >http://geekdinners.com >Microsoft MVP (C#), MCSD.NET, Author and Speaker > >The Silverlight Tour is coming to a city near you! > >-----Original Message----- >From: Discussion of advanced .NET topics. >[mailto:[EMAIL PROTECTED] On Behalf Of Frans Bouma >Sent: Friday, April 18, 2008 9:05 AM >To: ADVANCED-DOTNET@DISCUSS.DEVELOP.COM >Subject: Re: [ADVANCED-DOTNET] LINQ to SQL and inheritanc.... > >> I'm just having a mess about with LINQ and inheritance, I've basically >> created the canonical example, base class (lets say Animal), and derived >> class (lets say Dog) and set up the inheritance relations. >> >> I notice that once I set up the relationship the Derived class is not >> present in the data context as a "System.Data.Linq.Table<Dogs> Dogs". > > are they all mapped onto the same table with a discriminator? > >> hmmm....seems a little wierd, it would be nice to query and bind to Dogs >> directly (if you see what I mean). >> >> So I create a form and grid and bind to the Animals base Table (as it's >> the only one I've got and remove all the stuff I'm not interested >> in.....add something to the grid and of course it defaults to the base >> type. > > you can forget databinding if inheritance is involved: databinding >in >grids works with a single set of properties, and typically grids pick either >the first entry in the bound set to determine these or ask the ITypedList >implementation of the set, if available. > > if you have 2 subtypes of animal: Dog and JellyFish, both will have >their own unique properties: what should a grid do: display these columns or >not? If so, what should be happening when a row represents a dog and a >column >specific for jellyfish is changed? > > FB > >=================================== >This list is hosted by DevelopMentor. http://www.develop.com > >View archives and manage your subscription(s) at http://discuss.develop.com > >=================================== >This list is hosted by DevelopMentor® http://www.develop.com > >View archives and manage your subscription(s) at http://discuss.develop.com =================================== This list is hosted by DevelopMentor® http://www.develop.com View archives and manage your subscription(s) at http://discuss.develop.com
