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POHow to Work Around Limitations in Generic Type Constraints in C#?
 

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    <p>Okay I'm looking for some input, I'm pretty sure this is not currently supported in .NET 3.5 but here goes. </p> <p>I want to require a generic type passed into my class to have a constructor like this:</p> <pre><code>new(IDictionary&lt;string,object&gt;) </code></pre> <p>so the class would look like this</p> <pre><code>public MyClass&lt;T&gt; where T : new(IDictionary&lt;string,object&gt;) { T CreateObject(IDictionary&lt;string,object&gt; values) { return new T(values); } } </code></pre> <p>But the compiler doesn't support this, it doesn't really know what I'm asking.</p> <p>Some of you might ask, why do you want to do this? Well I'm working on a pet project of an ORM so I get values from the DB and then create the object and load the values.</p> <p>I thought it would be cleaner to allow the object just create itself with the values I give it. As far as I can tell I have two options:</p> <p>1) Use reflection(which I'm trying to avoid) to grab the PropertyInfo[] array and then use that to load the values.</p> <p>2) require T to support an interface like so:</p> <p>public interface ILoadValues { void LoadValues(IDictionary values); }</p> <p>and then do this</p> <pre><code>public MyClass&lt;T&gt; where T:new(),ILoadValues { T CreateObject(IDictionary&lt;string,object&gt; values) { T obj = new T(); obj.LoadValues(values); return obj; } } </code></pre> <p>The problem I have with the interface I guess is philosophical, I don't really want to expose a public method for people to load the values. Using the constructor the idea was that if I had an object like this</p> <pre><code>namespace DataSource.Data { public class User { protected internal User(IDictionary&lt;string,object&gt; values) { //Initialize } } } </code></pre> <p>As long as the <code>MyClass&lt;T&gt;</code> was in the same assembly the constructor would be available. I personally think that the Type constraint in my opinion should ask (Do I have access to this constructor? I do, great!)</p> <p>Anyways any input is welcome.</p>
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