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POEntity Framework lazy loading doesn't work from other thread
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copied!<p>I just found out that lazy loading in Entity Framework only works from the thread that created the <code>ObjectContext</code>. To illustrate the problem, I did a simple test, with a simple model containing just 2 entities : <code>Person</code> and <code>Address</code>. Here's the code :</p> <pre><code> private static void TestSingleThread() { using (var context = new TestDBContext()) { foreach (var p in context.Person) { Console.WriteLine("{0} lives in {1}.", p.Name, p.Address.City); } } } private static void TestMultiThread() { using (var context = new TestDBContext()) { foreach (var p in context.Person) { Person p2 = p; // to avoid capturing the loop variable ThreadPool.QueueUserWorkItem( arg => { Console.WriteLine("{0} lives in {1}.", p2.Name, p2.Address.City); }); } } } </code></pre> <p>The <code>TestSingleThread</code> method works fine, the <code>Address</code> property is lazily loaded. But in <code>TestMultiThread</code>, I get a <code>NullReferenceException</code> on <code>p2.Address.City</code>, because <code>p2.Address</code> is null.</p> <p>It that a bug ? Is this the way it's supposed to work ? If so, is there any documentation mentioning it ? I couldn't find anything on the subject on MSDN or Google...</p> <p>And more importantly, is there a workaround ? (other than explicitly calling <code>LoadProperty</code> from the worker thread...)</p> <p>Any help would be very appreciated</p> <p>PS: I'm using VS2010, so it's EF 4.0. I don't know if it was the same in the previous version of EF...</p>

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