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POIn Polymorphism only derived class can be the base class, what happens here?
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2011-10-18T10:55:53.520
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In Polymorphism I learned that only derived class can be the base class, but look at my example, a base class is now a derived class: <pre><code>static void Main() { Person a = new Customer(); //here a base class is a derived class Customer c = (Customer)a; } class Person { } class Customer : Person { } </code></pre> Why this is possible? The members of the derived class should not be discarded when instantiated on a base class? If I instantiate a derived class in a base class, the allocated memory size is the size of the derived class?
Tags
<c#><.net><oop><polymorphism>
Title
In Polymorphism only derived class can be the base class, what happens here?
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1. USAcaz Souza
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1. USAcaz Souza
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1. COJust say to yourself: "Client *IS A* Person" and it should all become clear: if Client is a Person, you can assign it to a Person object. If you know that this specific Person IS A Client, you can cast it back.
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 USKrumelur

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