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    copied!<p>By adding an intermediate class and a dictionary, <strong>specialization is possible</strong>.</p> <p>To specialize on T, we create an generic interface, having a method called (e.g.) Apply. For the specific classes that interface is implemented, defining the method Apply specific for that class. This intermediate class is called the traits class.</p> <p>That traits class can be specified as a parameter in the call of the generic method, which then (of course) always takes the right implementation.</p> <p>Instead of specifying it manually, the traits class can also be stored in a global <code>IDictionary&lt;System.Type, object&gt;</code>. It can then be looked up and voila, you have real specialization there.</p> <p>If convenient you can expose it in an extension method.</p> <pre><code>class MyClass&lt;T&gt; { public string Foo() { return "MyClass"; } } interface BaseTraits&lt;T&gt; { string Apply(T cls); } class IntTraits : BaseTraits&lt;MyClass&lt;int&gt;&gt; { public string Apply(MyClass&lt;int&gt; cls) { return cls.Foo() + " i"; } } class DoubleTraits : BaseTraits&lt;MyClass&lt;double&gt;&gt; { public string Apply(MyClass&lt;double&gt; cls) { return cls.Foo() + " d"; } } // Somewhere in a (static) class: public static IDictionary&lt;Type, object&gt; register; register = new Dictionary&lt;Type, object&gt;(); register[typeof(MyClass&lt;int&gt;)] = new IntTraits(); register[typeof(MyClass&lt;double&gt;)] = new DoubleTraits(); public static string Bar&lt;T&gt;(this T obj) { BaseTraits&lt;T&gt; traits = register[typeof(T)] as BaseTraits&lt;T&gt;; return traits.Apply(obj); } var cls1 = new MyClass&lt;int&gt;(); var cls2 = new MyClass&lt;double&gt;(); string id = cls1.Bar(); string dd = cls2.Bar(); </code></pre> <p>See this <a href="http://barendgehrels.blogspot.com/2010/07/c-specializations-by-traits-i.html" rel="noreferrer">link</a> to my recent blog and the follow ups for an extensive description and samples.</p>
 

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