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POReflection-generated and generic types
 

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    <p>I'm having yet another nasty moment with <code>Reflection.Emit</code> and type management.</p> <p>Say, I have a type named <code>MyType</code> which is defined in the dynamically generated assembly. Calling <code>MyType.GetMethods()</code> results in a <code>NotSupportedException</code>, which has reduced me to writing my own set of wrappers and lookup tables. However, the same is happening when I'm calling <code>GetMethods()</code> or any other introspecting methods on standard generic types which use my own types as generic arguments:</p> <ul> <li><code>Tuple&lt;int, string&gt;</code> => works fine</li> <li><code>Tuple&lt;int, MyType&gt;</code> => exception</li> </ul> <p>I can get the method list from the generic type definition:</p> <p><code>typeof(Tuple&lt;int, MyType).GetGenericTypeDefinition().GetMethods()</code></p> <p>However, the methods have generic placeholders instead of actual values (like <code>T1</code>, <code>TResult</code> etc.) and I don't feel like writing yet another kludge that traces the generic arguments back to their original values.</p> <p>A sample of code:</p> <pre><code>var asmName = new AssemblyName("Test"); var access = AssemblyBuilderAccess.Run; var asm = AppDomain.CurrentDomain.DefineDynamicAssembly(asmName, access); var module = asm.DefineDynamicModule("Test"); var aType = module.DefineType("A"); var tupleType = typeof(Tuple&lt;,&gt;); var tuple = tupleType.MakeGenericType(new [] { typeof(int), aType }); tuple.GetProperty("Item1"); // &lt;-- here's the error </code></pre> <p>So the questions are:</p> <ol> <li>How do I detect if a type is safe to call <code>GetMethods()</code> and similar methods on?</li> <li>How do I get the actual list of methods and their generic argument values, if the type is not safe?</li> </ol>
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    1. COPlease edit your question to include a short but *complete* program demonstrating the problem. Also, give more details about the `NotSupportedException` - is there nothing in the message?
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      1. USJon Skeet
    2. CO@JonSkeet, the exception simply says "The method is not supported" or something like that. I'm running a Russian version of Windows, so I don't know the exact message, but it contains no additional information. The stacktrace only has my `GetMethods()` and `System.Reflection.Emit.TypeBuilderInstantiation.GetMethods(BindingFlags bindingAttr)` inside it.
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    3. COIf you need those `MethodInfo`s (etc.) because you are still busy *building* the type, you do in fact have to keep track of the original `MethodBuilder`s (etc.) for use in method invocations and other emitted calls. If you need the `MethodInfo`s (etc.) after you've already called `CreateType`, then, as Eric answered, you can invoke those methods on the created type.
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      1. USKirk Woll
 

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