http://www.ideablade.com/forum/ This is an XML content feed of; DevForce Community Forum : DevForce 2009 : Four Step sample question Sun, 12 Apr 2026 04:39:31 -700 Wed, 24 Jun 2009 16:19:10 -700 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 9.69 360 www.ideablade.com/forum/RSS_post_feed.asp?TID=1337 http://www.ideablade.com/forum/forum_images/IdeaBlade_logo_tm.png http://www.ideablade.com/forum/ http://www.ideablade.com/forum/forum_posts.asp?TID=1337&PID=4847#4847 Author: GregD
Subject: 1337
Posted: 24-Jun-2009 at 4:19pm

Ben:

If you mean "why can't the result of the query be an IObservableCollection", I imagine the reason is that ObservableCollection is designed for UI purposes; whereas the query results may be needed for many different kinds of uses, for many of which a lighter-weight collection is entirely adequate.

You can, of course, refactor the foreach operation so you can do it a bit more succinctly.

>>
p.s. I would like to expand upon my question. If we are using a "Middleman" ObservableCollection (i.e. _employess or _orders) which areconnected to the UI but have no connection to the result coming formthe server, how is change on the UI going to make back to the server?
<<

Not sure which change you're talking about. All changes to the entities in the collection (Observable or otherwise) will get back to the server (and the backing store) via SaveChanges().
]]> Wed, 24 Jun 2009 16:19:10 -700 http://www.ideablade.com/forum/forum_posts.asp?TID=1337&PID=4847#4847 http://www.ideablade.com/forum/forum_posts.asp?TID=1337&PID=4813#4813 Author: BenHayat
Subject: 1337
Posted: 19-Jun-2009 at 12:32pm

Hi;

In the Four step sample, as we load the Employees and we get the result back (same thing for orders), why do we need to iterate through the result list and add them to an IObservableCollection? Why can't the result be an IObservableCollection, so we can directly connect it to grid's ItemsSource?

Thanks!

p.s. I would like to expand upon my question. If we are using a "Middle man" ObservableCollection (i.e. _employess or _orders) which are connected to the UI but have no connection to the result coming form the server, how is change on the UI going to make back to the server?
I think that's why I'm asking why can't we connect the UI to result, so any changes to UI is recognized by EM.
Thanks!

Edited by BenHayat - 20-Jun-2009 at 7:52am]]> Fri, 19 Jun 2009 12:32:06 -700 http://www.ideablade.com/forum/forum_posts.asp?TID=1337&PID=4813#4813