For a sample Extension method of strongly typed Includes: http://msmvps.com/blogs/matthieu/archive/2008/06/06/entityframework-include- with-func.aspx
Kim -----Original Message----- From: Discussion of advanced .NET topics. [mailto:[EMAIL PROTECTED] On Behalf Of Frans Bouma Sent: Tuesday, August 26, 2008 4:59 PM To: ADVANCED-DOTNET@DISCUSS.DEVELOP.COM Subject: SPAM-LOW: Re: [ADVANCED-DOTNET] typesafe ObjectQuery in entity framework... > I've been doing this for about 3 hours, so I may have the wrong end of the > stick. > > While doing the "hello world" type walkthrough I've come across.... > > ObjectQuery<Department> departmentQuery = > schoolContext.Department.Include("Course") > .OrderBy("it.Name"); > > Now I'm a bit confused as to what an object query is, but this doesn't > look nice...."Course" and "it.Name"...are going to give me runtime errors > if (when) something changes. > > I'm a bit confused as to how this sits with Linq....is there a Linq query > that I can use in the above which is typesafe and is of type > ObjectQuery<Department>? The '.Include("Course")' part won't be possible to make type safe, unless you write your own extension method, pass in an entity type and return a MethodCall expression to Include passing in the string. Why they haven't done that is beyond me, also why they haven't added more eager loading options like filters etc. The .OrderBy can be rewritten as: from d in schoolContext.Department.Include("Course") orderby d.Name ascending select d; at least, that's how standard linq queries would do it. FB ------------------------------------------------------------------------ Lead developer of LLBLGen Pro, the productive O/R mapper for .NET LLBLGen Pro website: http://www.llblgen.com My .NET blog: http://weblogs.asp.net/fbouma Microsoft MVP (C#) ------------------------------------------------------------------------ =================================== 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
