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POMVC 3 - The ObjectContext instance has been disposed and can no longer be used for operations that require a connection
 

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    <p>I'm very new to C# and MVC in general and I've been creating my own little blog site as a test project. Although most things are working up to this point, I have had problems selecting multiple columns from LINQ queries. It was only after stumbling on a question on SO that I realised I could use the generated entities classes as strongly-typed models to handle this. I've needed this as I've been creating a database layer (which is also something I've not used before) and trying to pass anonymous types through that layer didn't work. I understand why that was the case, so I'm satisfied that I'm heading in the right direction.</p> <p>However, this approach seems to have given me another problem. I've tried a simple test to retrieve 2 columns from my Categories table: CategoryID and Name. I initially tried the following:</p> <pre><code>using (MyEntities db = new MyEntities()) { var model = from c in db.Categories select new Category { CategoryID = c.CategoryID, Name = c.Name }; return View(model); } </code></pre> <p>This gave me the ObjectContext is disposed error when trying to iterate over the model in the view. After reading <a href="https://stackoverflow.com/questions/2884332">this question</a>, I tried moving the return statement outside of the using block and calling AsEnumerable() on the model like so:</p> <pre><code>IEnumerable&lt;Category&gt; model; using (MyEntities db = new MyEntities()) { model = from c in db.Categories select new Category { CategoryID = c.CategoryID, Name = c.Name }; } return View(model.AsEnumerable()); </code></pre> <p>However, this is still giving me the same ObjectContext is disposed error when I try to iterate over the model in the view. So now I don't understand why I'm getting the error. I've even tried removing the using directive completely but that gives me a different error:</p> <p>"The entity or complex type 'MyProjectModel.Category' cannot be constructed in a LINQ to Entities query."</p> <p>If it helps, here's the relevant code for my view:</p> <pre><code>@model IEnumerable&lt;MyProject.Models.Category&gt; @foreach (var category in Model) { &lt;p&gt;@category.Name&lt;/p&gt; } </code></pre> <p>Would someone be kind enough to enlighten me as to what I'm missing?</p> <p>Thanks.</p>
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