Databases
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    <p>Be eager in the controller and call <code>.ToList()</code> before disposing in order to schedule the execution of the query immediately before you have left the <code>using</code> block (as after that it is too late, the context is gone):</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.ToList()); // &lt;-- .ToList() here } </code></pre> <p>Now, while this will solve your particular problem, what developers or dependency injection frameworks usually do is to instantiate the <code>DbContext</code> inside the <code>BeginRequest</code> event, store it inside the <code>HttpContext.Items</code> so that it is available throughout the execution of the entire request and inside the <code>EndRequest</code> method, retrieve it from <code>HttpContext</code> and dispose it.</p> <hr> <p>UPDATE:</p> <p>Also it is a good practice to use a view model containing only the properties you would like to use in this particular view:</p> <pre><code>public class CategoryViewModel { public int Id { get; set; } public string Name { get; set; } } </code></pre> <p>and then inside your action:</p> <pre><code>public ActionResult Index() { using (MyEntities db = new MyEntities()) { var model = from c in db.Categories select new CategoryViewModel { Id = c.CategoryID, Name = c.Name }; return View(model.ToList()); } } </code></pre> <p>and in the view:</p> <pre><code>@model IEnumerable&lt;MyProject.Models.CategoryViewModel&gt; @foreach (var category in Model) { &lt;p&gt; Id: @category.Id Name: @category.Name &lt;/p&gt; } </code></pre>
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    1. USDarin Dimitrov
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    1. CO`.ToList()` is (slightly) faster
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    2. COHi Darin, thanks for the response but that gives me the complex type cannot be constructed in a LINQ to Entities query, error. I don't know if it makes a difference but the Category class was auto-generated for me as part of my entities model.
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    3. CO@johnh, I am really not familiar with LINQ to Entities but anyway, try like this directly `return View(db.Categories.ToList());` inside the `using` block.
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Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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