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Entity Framework POCO and WCF Data Service - Lazy-loading (expand?) related entities?

Posted By:      Posted Date: September 10, 2010    Points: 0   Category :ASP.Net
I've followed ScottGu article on creating an Entity Framework POCO classes for NerdDinners (right now there are only 2 classes, Dinner and RSVP. I then created a WCF Data Service class, which points to my EF class (NerdDinner), everything is working fine, except I can't lazy-load or expand related entities. For example, I want to get all load all the Dinners and their related RSVPs, something like this throw an error:var result = (from d in db.Dinners.Expand("RSVPs")                      select d);The error is a null reference error:at System.Data.Services.Serializers.SyndicationSerializer.WriteObjectProperties(IExpandedResult expanded, Object customObject, ResourceType resourceType, Uri absoluteUri, String relativeUri, SyndicationItem item, DictionaryContent content, EpmSourcePathSegment currentSourceRoot) at System.Data.Services.Serializers.SyndicationSerializer.WriteEntryElement(IExpandedResult expanded, Object element, ResourceType expectedType, Uri absoluteUri, String relativeUri, SyndicationItem target) ... ... ...Any idea why or what I need to do to load related contents?Thank you very much.

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