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POC# Generic Class with "specialized" constructor
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  1. POC# Generic Class with "specialized" constructor
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    copied!<p>I have a class like the following:</p> <pre><code>public class DropDownControl&lt;T, Key, Value&gt; : BaseControl where Key: IComparable { private IEnumerable&lt;T&gt; mEnumerator; private Func&lt;T, Key&gt; mGetKey; private Func&lt;T, Value&gt; mGetValue; private Func&lt;Key, bool&gt; mIsKeyInCollection; public DropDownControl(string name, IEnumerable&lt;T&gt; enumerator, Func&lt;T, Key&gt; getKey, Func&lt;T, Value&gt; getValue, Func&lt;Key, bool&gt; isKeyInCollection) : base(name) { mEnumerator = enumerator; mGetKey = getKey; mGetValue = getValue; mIsKeyInCollection = isKeyInCollection; } </code></pre> <p>And I want to add a convenience function for Dictionaries (because they support all operations efficiently on their own).</p> <p>But the problem is that such a constructor would only specify Key and Value but not T directly, but T is just KeyValuePair. Is there a way to tell the compiler for this constructor T is KeyValuePair, like:</p> <pre><code>public DropDownControl&lt;KeyValuePair&lt;Key, Value&gt;&gt;(string name, IDictionary&lt;Key, Value&gt; dict) { ... } </code></pre> <p>Currently I use a static Create function as workaround, but I would like a direct constructor better.</p> <pre><code>public static DropDownControl&lt;KeyValuePair&lt;DKey, DValue&gt;, DKey, DValue&gt; Create&lt;DKey, DValue&gt;(string name, IDictionary&lt;DKey, DValue&gt; dictionary) where DKey: IComparable { return new DropDownControl&lt;KeyValuePair&lt;DKey, DValue&gt;, DKey, DValue&gt;(name, dictionary, kvp =&gt; kvp.Key, kvp =&gt; kvp.Value, key =&gt; dictionary.ContainsKey(key)); } </code></pre>
 

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