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copied!<p>First, when casting you need a type (double, int); typeof takes a type argument and returns a class of type Type.</p> <pre><code> object x = 0.0; Type t = typeof(double); double y = x as t; //does not compile - t is not a type - it's an instance of type Type double y = x as typeof(double); //same as above double y = x as double; //compiles - double is a type Type z = x as Type; //compiles - Type is a type </code></pre> <p>Second, here is some example code:</p> <pre><code>using System; using System.Collections.Generic; using System.Collections; using System.Reflection; using System.Diagnostics; namespace TryThis { public interface IContainer<T> { IEnumerable<IContent<T>> Contents { get; } } public interface IContent<T> { T GetMyContent(); } public interface IProperty { } public class Content<T> : IContent<T> { T m_content = default(T); public T GetMyContent() { return m_content; } public Content(T val) { m_content = val; } } public class Contents<T> : IEnumerable<IContent<T>> { List<IContent<T>> m_contents = new List<IContent<T>>(); IEnumerator<IContent<T>> IEnumerable<IContent<T>>.GetEnumerator() { return m_contents.GetEnumerator(); } IEnumerator IEnumerable.GetEnumerator() { return m_contents.GetEnumerator(); } public Contents(params T[] contents) { foreach (T item in contents) m_contents.Add(new Content<T>(item)); } } public class TestGenericContent : IContainer<int> { public IContainer<int> GetContainer(IProperty property) { return this; } public IEnumerable<IContent<int>> Contents { get { return new Contents<int>(1, 2, 3); } } } public static class TryThisOut { static void Test2(object o) { Type t = o.GetType(); Type tInterface = t.GetInterface("IContainer`1"); //could be null if o does not implement IContainer<T> Type tGenericArg = tInterface.GetGenericArguments()[0]; //extracts T from IContainer<T> MethodInfo info = t.GetMethod("GetContainer"); IProperty propArg = null; //null in this example object oContainer = info.Invoke(o, new object[] { propArg }); PropertyInfo prop = tInterface.GetProperty("Contents"); object oContents = prop.GetGetMethod().Invoke(oContainer, null); //oContents is of type IEnumerable<IContent<T>>, which derives from IEnumerable, so we can cast IEnumerable enumeratedContents = oContents as IEnumerable; MethodInfo getContentItem = typeof(IContent<>).MakeGenericType(tGenericArg).GetMethod("GetMyContent"); foreach (object item in enumeratedContents) { object oContentItem = getContentItem.Invoke(item, null); Debug.Print("Item {0} of type {1}", oContentItem, oContentItem.GetType()); //... } } public static void Test() { object o = new TestGenericContent(); Test2(o); } } } </code></pre>

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