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POPros and cons of 'new' properties in C# / .Net?
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copied!<p>Considering the following sample code:</p> <pre><code>// delivery strategies public abstract class DeliveryStrategy { ... } public class ParcelDelivery : DeliveryStrategy { ... } public class ShippingContainer : DeliveryStrategy { ... } </code></pre> <p>and the following sample Order class:</p> <pre><code>// order (base) class public abstract class Order { private DeliveryStrategy delivery; protected Order(DeliveryStrategy delivery) { this.delivery = delivery; } public DeliveryStrategy Delivery { get { return delivery; } protected set { delivery = value; } } } </code></pre> <p>When i derive a new type of order class, it will inherit the Delivery property of type DeliveryStrategy.</p> <p>Now, when it is given that CustomerOrders must be delivered using the ParcelDelivery strategy, we could consider '<strong>new</strong>'ing the Delivery property in the CustomerOrder class:</p> <pre><code>public class CustomerOrder : Order { public CustomerOrder() : base(new ParcelDelivery()) { } // 'new' Delivery property public new ParcelDelivery Delivery { get { return base.Delivery as ParcelDelivery; } set { base.Delivery = value; } } } </code></pre> <p>(The CustomerOrder obviously needs to ensure that is compatible (polymorph) with Order)</p> <p>This allows direct usage of the ParcelDelivery strategy on CustomerOrder without the need for casting.</p> <p>Would you consider using this pattern? why / why not?</p> <p><strong>Update</strong>: i came up with this pattern, instead of using generics, because i want to use this for multiple properties. I don't want to use generic type arguments for all these properties</p>

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