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POMethod throws null reference exception after returning non-null value
 

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  1. POMethod throws null reference exception after returning non-null value
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    <p>I have a service method that very simply gets the information for all stores in the database. It maps the stores from EF using Auto Mapper, and returns a generic response of type StoreDTO (a simple POCO). </p> <p>The problem is this: the method executes just fine, I step through all the way to the end. Every property in <code>response</code> has a value, nothing is null. The list is populated with items, the items in the list are valid, etc etc.</p> <p>But the following code throws a NullReferenceException as soon as <code>GetAllStores</code> returns:</p> <pre><code>ListResponseDTO&lt;StoreDTO&gt; allStores = Services.Stores.Stores.GetAllStores(); </code></pre> <p>EDIT: Here is a screenshot of the debugger, right when it is returning. You can see in the watch window that the values look kosher: <a href="http://i.imgur.com/rd853.png" rel="nofollow">http://i.imgur.com/rd853.png</a></p> <p>Any help is greatly appreciated. Here is the code from the method:</p> <pre><code> public static ListResponseDTO&lt;StoreDTO&gt; GetAllStores() { ListResponseDTO&lt;StoreDTO&gt; response = new ListResponseDTO&lt;StoreDTO&gt;("Get Stores not successful"); try { response.Items = new List&lt;StoreDTO&gt;(); using (DomainEntities db = new DomainEntities(Global.ConnectionString)) { foreach (var IndividualStore in db.Stores) { Mapper.CreateMap&lt;Store, StoreDTO&gt;(); var IndividualStoreDTO = Mapper.Map&lt;Store, StoreDTO&gt;(IndividualStore); response.Items.Add(IndividualStoreDTO); } } response.Message = "Store(s) retrieved successfully"; response.Success = true; } catch (Exception ex) { Logging.Log("Get All Stores", response.Message + " " + ex.ToString(), Logging.LogPriority.Error, "Store Operations"); } return response; } </code></pre> <p>Here is the generic DTO definition:</p> <pre><code>public class ListResponseDTO&lt;DtoType&gt; : ResponseDTO { public ListResponseDTO() : base() { Items = new List&lt;DtoType&gt;(); } public ListResponseDTO(string defaultMessage) : base(defaultMessage) { Items = new List&lt;DtoType&gt;(); } public List&lt;DtoType&gt; Items; } </code></pre> <p>In case you were wondering, <code>ResponseDTO</code> has two properties:</p> <p><code>bool Success</code></p> <p><code>string Message</code></p> <p>Here is the exception details, I'm afraid it's not too helpful:</p> <pre><code>System.NullReferenceException was unhandled by user code Message=Object reference not set to an instance of an object. Source=Infinity StackTrace: at PLM.Infinity.Default.GetDrawersForUser() in C:\Users\jlucas\Documents\Visual Studio 2010\PLM Source Control\Utilities\InfinityInterface\Infinity\Default.aspx.cs:line 96 InnerException: </code></pre>
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    1. USlucrativelucas
    1. USlucrativelucas
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      1. POMethod throws null reference exception after returning non-null value
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    1. COTry removing the try/catch and see what happens
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      1. USJohn Saunders
    2. COSame thing. It doesn't throw an exception in the method, it only throws it after the method returns.
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      1. USlucrativelucas
    3. COWhat does the GetAllStores Method look like the only way that you are getting Null after returning is because you are either newing it up again or you have some odd recursive method / property call that resets the object also why is this line needed ListResponseDTO<StoreDTO> response = new ListResponseDTO<StoreDTO>("Get Stores not successful");
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      1. USMethodMan
 

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