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POHow do you use foreach on a base class using generics?
 

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  1. POHow do you use foreach on a base class using generics?
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    <p>This question is as a result of trying <a href="https://stackoverflow.com/users/22656/jon-skeet">Jon Skeet's</a> answer to <a href="https://stackoverflow.com/questions/944296/">this question</a>.</p> <p>So I have the following code based in the question and answer from the above question link.</p> <pre><code> public abstract class DeliveryStrategy { } public class ParcelDelivery : DeliveryStrategy { } public class ShippingContainer : DeliveryStrategy { } public abstract class Order&lt;TDelivery&gt; where TDelivery : DeliveryStrategy { private TDelivery delivery; protected Order(TDelivery delivery) { this.delivery = delivery; } public TDelivery Delivery { get { return delivery; } set { delivery = value; } } } public class CustomerOrder : Order&lt;ParcelDelivery&gt; { public CustomerOrder() : base(new ParcelDelivery()) { } } public class OverseasOrder : Order&lt;ShippingContainer&gt; { public OverseasOrder() : base(new ShippingContainer()) { } } </code></pre> <p>I'm trying understand generics more to improve my skill set, so I have the question of: Now how can I use foreach to loop through a collection of "Orders"? I'm using C#2.0.</p> <p>Code Example of what I'm trying to do (does not compile).</p> <pre><code>List&lt;Order&gt; orders = new List&lt;Order&gt;(); orders.Add(new CustomerOrder()); orders.Add(new CustomerOrder()); orders.Add(new OverseasOrder()); orders.Add(new OverseasOrder()); foreach (Order order in orders) { order.Delivery.ToString(); } </code></pre> <p><b>EDIT: Added OverseasOrder to give a better example.</b></p>
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    1. COJust out of curiosity...what is the compiler error you are getting?
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    2. COUsing the generic type 'WindowsApplication34.Order<TDelivery>' requires '1' type arguments
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