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copied!<blockquote> <p>The idea is to be able to determine the true type of the an object in a method parameter</p> </blockquote> <p>That's easy enough (and you're already doing it).</p> <pre><code>Type actualType = param.GetType(); </code></pre> <p>That will get you the actual concrete type of the object</p> <blockquote> <p>and then cast that object as it's true type</p> </blockquote> <p>This is where things come off the rails a bit. The casting operator in C# (usage of which is what people refer to as "casting") can do two things:</p> <ol> <li>Use type-specific explicit conversions to create a new object by applying the conversion to the existing object (note that this is a <em>new</em> reference that is created; the original object's type is never changed)</li> <li>Allow the developer to reference an object as a type that is at a different level in its inheritance hierarchy than is currently provided (or an interface that is implemented on a type that is lower in the hierarchy than is currently referenced)</li> </ol> <p>In your case, the first option is right out; the casting operator, like all operators, is not polymorphic. That is, an operator is only applied if it is defined on the <em>type</em> that is being referenced, not the <em>object</em> that's being referenced. If you'd like further clarification on this, let me know, but I don't think it's germane to your question so I'm not going to go into it further unless asked.</p> <p>The second option is the only option that could realistically apply to you, but consider the only two reasons you would want to do this:</p> <ol> <li>So that you can refer to the object as a specific concrete type that is at a lower level than is currently provided (in your case, your object is an <code>object</code>, so that's pretty much as high as it goes)</li> <li>So that you can refer to an object as a type that is <em>higher</em> in the hierarchy so that you can bypass hidden (but not overridden) members.</li> </ol> <p>(The vast majority of casts are for reason #1)</p> <p>The reason you would want to use either of those options is so that you can have a strongly-typed object and use the various members defined on that type. But all of these things only apply to types that you <em>know</em> when you're writing the code. It doesn't make sense to cast to a type that is unknown at compile time, as casting doesn't do anything to the actual object (it is, and shall remain, its true type; the only thing that changes is the type of the <em>variable</em> by which you reference the object).</p> <p>If you can provide a further fleshed-out example of what you're actually trying to do (complete with code as you'd either like or expect it to work), I might be able to provide something modeled a little closer to what you want, but as it's described this is as specific as I can get.</p>

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