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How to call a method using reflection using lambda expression as parameter?

I want to do this:

MethodInfo m = myList.GetType().GetMethod("ConvertAll", System.Reflection.BindingFlags.InvokeMethod).MakeGenericMethod(typeof(object));
List<object> myConvertedList = (List<object>)m.Invoke(myList, new object[]{ (t => (object)t)});

myList is a general list of a certain type (unknown to the application), and I want to convert it to a list of objects to perform some operations.

However, this fails with this error: "It is not possible to convert the lambda expression to the type" object "because it is not a delegate type"

Can you help me find what is wrong? Am I trying to do something impossible?

Is there any other way to achieve the same?

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2 answers

, , , .

, , :

public static List<object> ConvertToListOfObjects<T>(List<T> list)
{
    return list.ConvertAll<object>(t => t);
}

:

MethodInfo method = typeof(Foo).GetMethod("ConvertToListOfObjects",
    BindingFlags.Static | BindingFlags.Public);
Type listType = list.GetType().GetGenericArguments()[0];
MethodInfo concrete = method.MakeGenericMethod(new [] { listType });
List<object> objectList = (List<object>) concrete.Invoke(null, 
                                                   new object[]{list});

:

using System;
using System.Reflection;
using System.Collections.Generic;

class Test
{
    public static List<object> ConvertToListOfObjects<T>(List<T> list)
    {
        return list.ConvertAll<object>(t => t);
    }

    static void Main()
    {
        object list = new List<int> { 1, 2, 3, 4 };

        MethodInfo method = typeof(Test).GetMethod("ConvertToListOfObjects",
            BindingFlags.Static | BindingFlags.Public);
        Type listType = list.GetType().GetGenericArguments()[0];
        MethodInfo concrete = method.MakeGenericMethod(new [] { listType });
        List<object> objectList = (List<object>) concrete.Invoke(null,
                                                    new object[] {list});

        foreach (object o in objectList)
        {
            Console.WriteLine(o);
        }
    }
}
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, . , :

List<object> myConvertedList = (List<object>)m.Invoke(myList, new object[]{ new Func<YourType, object>(t => (object)t)});
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