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POAny suitable patterns for this problem?
 

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  1. POAny suitable patterns for this problem?
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    <p>I have a situation in which I am attempting to keep my model and implementation as loosely coupled as possible, however I am faced with a situation where the coupling could potentially get a lot closer than I want.</p> <p>I have a selection of 'Model' classes, all implementing interfaces. Additionally I have 'Data Access' classes, which provide a number of functions, one of which is decoding integer lookup values into their full 'object' representation.</p> <p>Within my model classes I want to provide access to these decoded values without requiring the model to know about the data access classes.</p> <p>A simplified example is:</p> <pre><code>/// Core classes -- class Car : ICar { public int MakeId { get {...} set { ... } } public IMakeInfo Make { get {...} } public string Registration { get { ... } set { ... } } public int CurrentOwnerId { get { ... } set { ... } } public IPerson CurrentOwner { get { ... } } } class MakeInfo : IMakeInfo { public string Name { ... } public int Id { ... } public decimal Weight { ... } // etc etc } /// Data Access Classes -- class ResolveMake { public IMakeInfo GetMakeInfo(int id) { // Implementation here... } } </code></pre> <p>How do I enable the <code>Car</code> class to provide the <code>IMakeInfo</code> object to any consuming classes without directly making it aware of the ResolveMake class? In the actual instance I am working with the Car class is not in the same namespace as the ResolveMake class and it contains no references to any instances of it.</p> <p>Some of my options:</p> <ul> <li>Implement a delegate in <code>Car</code> which can be supplied with an instance of the <code>GetMakeInfo</code> method.</li> <li>Some kind of dependency injection</li> <li>Closely couple Car to ResolveMake and be done with it.</li> <li>Any other options?</li> </ul> <p>Any suggestions welcome!</p>
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    1. USAsh
    1. USAsh
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      1. POAny suitable patterns for this problem?
      1. USJon Limjap
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    1. COCould you pass a `ResolveMake` instance to `Car` in some way to have it modify that instance and return it with a call to `Make`?
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      1. POAny suitable patterns for this problem?
      1. USMike Mazur
    2. COIs there a reason why you use interfaces for your models? This is often considered an anti pattern, e.g http://www.lostechies.com/blogs/jagregory/archive/2009/05/09/entity-interface-anti-pattern.aspx.
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      1. POAny suitable patterns for this problem?
      1. USBengtBe
    3. CO@BengtBe - Although I agree this does stink of anti-pattern the example I've given is purely just that, the real situation makes good use of the interfaces and the resulting abstraction.
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      1. USAsh
 

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