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POCast List<object> to unknown T[] using reflection
 

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    <p>I found something similar on another question but i couldnt solve my problem as i'm still quite new in c#.</p> <p>i have</p> <pre><code>System.Type type; // for example int[] System.Type elementType = type.GetElementType(); //for example int </code></pre> <p>and a List that i need to cast to int[]</p> <pre><code>object valueObj; //is my List&lt;object&gt; i want to cast to int[] </code></pre> <p>I'm trying the following:</p> <pre><code>MethodInfo castMethod = typeof(Enumerable).GetMethod("Cast") .MakeGenericMethod( new System.Type[]{ elementType } ); MethodInfo toArrayMethod = typeof(Enumerable).GetMethod("ToArray") .MakeGenericMethod( new System.Type[]{ elementType } ); var castedObjectEnum = castMethod.Invoke(null, new object[] { valueObj }); var castedObject = toArrayMethod.Invoke(null, new object[] { castedObjectEnum }); </code></pre> <p>in the last line i get this runtime exception</p> <p>InvalidCastException: Cannot cast from source type to destination type. System.Linq.Enumerable+c__Iterator0<code>1[System.Int32].MoveNext () System.Collections.Generic.List</code>1[System.Int32].AddEnumerable (IEnumerable`1 enumerable)</p> <p>as a last thing i need to assign the casteObject to a privateField using</p> <pre><code>field.SetValue(this, castedObject); </code></pre> <p>Edit: I will try and get more info on that but to better explain what i'm trying to do i will explain the use case.</p> <p>i serialize to disk in json some class fields, and then when i deserialize i get back a List where i serialize a base array of int/bools/string</p> <p>I'm doing the serialization and deserialization by marking fields with a custom attribute, and i want to be able to serialize both Array and Lists of any basic type</p> <p>i will double check and get with more info</p>
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    1. USUltrakorne
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    1. CORather than posting *snippets* of the broken code, please work this into a short but complete console app demonstrating the problem. It will make it *much* easier for other people to help you.
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      1. USJon Skeet
    2. COAre they actually all int's? Are they something which you could *convert* to an int? Why do you not know the actual types at this point in the code? Reflection should be rarely needed, so the answers to all of these will help answer your question.
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      1. USuser7116
    3. COi dont know the type, i added a bit of explanation on the use case. @jonSkeet, i will double check and try to isolate the issue.
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