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    <p>It says what the error is in the error message.</p> <p>You have a class <code>My_Entity_Name</code>. An instance of <code>My_Entity_Name</code> is assigned to the property <code>self.entityArray</code>. When you do <code>for (MyEntityType *entityType in self.entityArray)</code>, it passes the <code>-countByEnumeratingWithState:objects:count:</code> message to the instance, and you get the unrecognized selector error.</p> <p>I would look for places where the the value is assigned (either <code>self.entityArray = …</code> or <code>[self setEntityArray:…]</code>) to figure out how <code>self.entityArray</code> is getting the bad value. Perhaps you should post how you are doing the fetch, or if there are other ways that <code>self.entityArray</code> can get assigned a value.</p> <hr> <p><strong>UPDATE</strong></p> <p>I'm not sure what <code>-[Singleton retrieveEntity:]</code> does. It's not a class that's a part of the standard framework, and I don't know of any 3rd party library which uses such generic naming.</p> <p>What I can tell you is that based on the method name <code>-retrieveEntity:</code>, it looks like it returns a single object not an array of objects. Usually methods that return arrays are pluralised, so I would have expected the name to be more like <code>-retrieveEntities:</code>.</p> <p>You got an exception because is because <code>self.entityArray</code> doesn't contain an <code>NSArray</code>. The method name doesn't look like it would return an array.</p> <p>Are you absolutely sure that <code>[[Singleton sharedInstance] retrieveEntity:…]</code> should return an <code>NSArray</code>? Perhaps you should post the code for <code>-retrieveEntity:</code>.</p> <hr> <p><strong>UPDATE</strong></p> <p>You are not returning an array.</p> <pre><code>NSArray *items = [context executeFetchRequest:fetchRequest error:&amp;error]; if ([items count]&gt;0) { return items[0]; } else { return nil; } </code></pre> <p>If the items array has any elements, then the first element is returned. This is what <code>items[0]</code> does.</p> <p>If you want to return the array change it to:</p> <pre><code>NSArray *items = [context executeFetchRequest:fetchRequest error:&amp;error]; if ([items count]&gt;0) { return items; } else { return nil; } </code></pre> <p>Notice I've replaced <code>return items[0];</code> (return the first element of the array) with <code>return items;</code> (return the whole array).</p>
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    1. POGetting runtime error when doing fast enumeration over an NSArray of entities from Core Data in iOS
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    1. USJeffery Thomas
    1. USJeffery Thomas
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    1. COThanks for your answer. I've added my code showing how I populate my array from the fetch.
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    2. CO[Singleton retrieveEntity] is my Singleton instance which calls my method to retrieve the results from Core Data. I've changed the name as you suggested to be more accurate on its functionality (i.e. making it plural because it is supposed to return multiple results. I've also included the method that does the actual fetching.
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    3. COWould I be receiving this error if I my array contained only one object? I'm asking this because if I do an NSLog:(@"Number of objects in array are: %d", [self.entityArray count]); I notice that I get the same error for this line also.
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