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PODbDataConttoller UpdateEntity throws an exception
 

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    <p>I'm experimenting with VS 2011 Beta and EF and I'm having trouble with UpdateEntity, but InsertEntity and DeleteEntity works fine.</p> <p>The problem is that when I call UpdateEntity I get an "object reference not set to an instace of an object" exception.</p> <p>Seems to happen with all the models in my project.</p> <p>To try to isolate the problem, I created a really simple DTO class with basic properties, but I get the same error when I try to call UpdateEntity on that object. Here's my code:</p> <p>The Test DTO:</p> <pre><code> [Table("Test")] public class Test { [Key, Column] public int Id { get; set; } [Column] public string TestMember { get; set; } } </code></pre> <p>I've got a DbDataController with the following methods:</p> <pre><code> public void InsertTest(Test entity) { InsertEntity(entity); } public void UpdateTest(Test entity) { UpdateEntity(entity); } public void DeleteTest(Test entity) { DeleteEntity(entity); } </code></pre> <p>Finally, I've defined this Test object in my DbContext class:</p> <pre><code>public DbSet&lt;Test&gt; Test { get; set; } </code></pre> <p>Of course I've got a table called Test in my database, this is the create script for the table:</p> <pre><code> CREATE TABLE [dbo].[Test]( [ID] [int] IDENTITY(1,1) NOT NULL, [TestMember] [nvarchar](50) COLLATE Icelandic_CI_AS NOT NULL, CONSTRAINT [PK_Test] PRIMARY KEY CLUSTERED ( [ID] ASC )WITH (IGNORE_DUP_KEY = OFF) ON [PRIMARY] ) ON [PRIMARY] </code></pre> <p>I can successfully insert new test objects to the database:</p> <pre><code> using (DataController dataSource = new DataController()) { Test test = new Test(); test.Id = 1; test.TestMember = "test2"; dataSource.InsertTest(test); dataSource.SaveChanges(); } </code></pre> <p>I can then easily delete it from the database:</p> <pre><code> using (DataController dataSource = new DataController()) { Test test = new Test(); test.Id = 1; test.TestMember = "test2"; dataSource.DeleteTest(test); dataSource.SaveChanges(); } </code></pre> <p>But if I try to do this:</p> <pre><code> using (DataController dataSource = new DataController()) { Test test = new Test(); test.Id = 1; test.TestMember = "UpdatedTest"; dataSource.UpdateTest(test); dataSource.SaveChanges(); } </code></pre> <p>I get a "Object reference not set to an instance of an object." exception at this line here:</p> <p><strong>UpdateEntity(entity);</strong></p> <p>inside the UpdateTest method in the DataController.</p> <p>There is no InnerException and the stack trace is not exactly helpful:</p> <blockquote> <p>at System.Web.Http.Data.EntityFramework.DbDataController<code>1.UpdateEntity(Object entity) at Hot.Web.Controllers.DataController.UpdateTest(Test entity) in c:\......\DataController.cs:line 48 at Hot.Web.Controllers.UserManagementController.EditProfile() in c:\.......\UserManagementController.cs:line 223 at lambda_method(Closure , ControllerBase , Object[] ) at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters) at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary</code>2 parameters) at System.Web.Mvc.Async.AsyncControllerActionInvoker.&lt;>c_<em>DisplayClass42.b</em>_41() at System.Web.Mvc.Async.AsyncResultWrapper.&lt;>c_<em>DisplayClass8<code>1.&lt;BeginSynchronous&gt;b__7(IAsyncResult _) at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult</code>1.End() at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult) at System.Web.Mvc.Async.AsyncControllerActionInvoker.&lt;>c</em>_DisplayClass37.&lt;>c_<em>DisplayClass39.b</em>_33() at System.Web.Mvc.Async.AsyncControllerActionInvoker.&lt;>c_<em>DisplayClass4f.b</em>_49()</p> </blockquote> <p>Anyone got any clue what could be wrong?</p>
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