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copied!<p>Nope, there's no way of doing this. Any instance of <code>DictHandler</code> <em>must</em> know the exact type of <code>T</code>, including the type of <code>TKey</code> and <code>TValue</code>.</p> <p>You can use type inference to reduce how often you need to explicitly specify type arguments though, if you actually <em>have</em> an instance of the relevant dictionary. For example:</p> <pre><code>public static class DictHandler { public static DictHandler<T, TKey, TValue> CreateHandler<T, TKey, TValue> (T dictionary1, Dictionary<TKey, TValue> dictionary2) where T : Dictionary<TKey, TValue> { return new DictHandler<T, TKey, TValue>(); } } public class DictHandler<T, TKey, TValue> where T : Dictionary<TKey, TValue> { } </code></pre> <p>Then create it like this:</p> <pre><code>Dictionary<string, int> dict = new Dictionary<string, int>(); var handler = DictHandler.CreateHandler(dict, dict); </code></pre> <p>I believe the reason you have to have the two parameters is so that the arguments (which are all that gets used in type inference) end up corresponding with parameters which <em>directly</em> mention the type parameters. I'm not entirely sure though - and this is certainly somewhat ugly.</p> <p>Another alternative is to create a base type or base interface for A which <em>isn't</em> generic. For example, in this case (assuming we could control Dictionary) we'd create:</p> <pre><code>public interface INonGenericDictionary { // Members which don't rely on the type parameters } public class Dictionary<TKey, TValue> : INonGenericDictionary { ... } </code></pre> <p>then</p> <pre><code>public class DictHandler<T> where T : INonGenericDictionary { ... } </code></pre> <p>We can't really tell whether that's suitable in your case, but it <em>may</em> be.</p>

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