How to call a general method through reflection

Question

can a reflection method be called with an argument of "explict type" <S>definition
for example oObject.Cast<S>()?

Where:

IList <P> oObject = new List <P>();

I tried using

oObject.getType().InvokeMember( "Cast", BindingFlags.InvokeMethod, null, oObject, null)

but it doesn’t work, does anyone know why?

---

Here is the full test code, but it still doesn't work. The last line always throws an exception. Is it possible to make it work?

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Reflection;

namespace reflection_tester
{
    class CBase
    {
        public string Ja = "I am the base";
    }

    class MyClass01 : CBase
    {
        public string _ID;

        public string ID
        {
            get { return _ID; }
            set { _ID = value; }
        }
    }

    class Program
    {

        public static object wrapper()
        {
            //return a list of classes MyClass01

            IList<MyClass01> lstClass01 = new List<MyClass01>();

            MyClass01 oClass01a = new MyClass01();
            oClass01a.ID = "1";

            MyClass01 oClass01b = new MyClass01();
            oClass01b.ID = "2";

            lstClass01.Add(oClass01a);
            lstClass01.Add(oClass01b);

            return lstClass01;
        }

        static void Main(string[] args)
        {

            MyClass01 oMy1 = new MyClass01();
            oMy1._ID = "1";

            MyClass01 oMy2 = new MyClass01();
            oMy2._ID = "3";

            IList<MyClass01> oListType01 = new List<MyClass01>();

            oListType01.Add(oMy1);
            oListType01.Add(oMy2);

            object oObjectType = new object();

            oObjectType = oListType01;

            /* this works */
            IEnumerable<CBase> enumList = oListType01.Cast<CBase>();

            MethodInfo mInfo = typeof(System.Linq.Enumerable).GetMethod("Cast", new[] { typeof(System.Collections.IEnumerable) }).MakeGenericMethod(typeof(CBase));

            /* this does not work, why ? throws exception */
            IEnumerable<CBase> enumThroughObject = (IEnumerable<CBase>)mInfo.Invoke(oObjectType, null);

            return;
        }
    }
}

Answer 1

The Cast extension method lives in the Enumerable class, and you need to call MakeGenericMethod:

typeof(System.Linq.Enumerable)
    .GetMethod("Cast", new []{typeof(System.Collections.IEnumerable)})
    .MakeGenericMethod(typeof(S))
    .Invoke(null, new object[] { oObjectType })

the update: . Since this method is static, the first parameter to Invoke should benull

Answer 2

, Type.MakeGenericType