Immutable List

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

namespace ImmutableList
{
    public class ImmutableListMain
    {
        public static void Main()
        {
            Type immutableList = typeof(ImmutableList);
            FieldInfo[] fields = immutableList.GetFields();
            if (fields.Length < 1)
            {
                throw new Exception();
            }
            else
            {
                Console.WriteLine(fields.Length);
            }

            MethodInfo[] methods = immutableList.GetMethods();
            bool containsMethod = methods.Any(m => m.ReturnType.Name.Equals("ImmutableList"));
            if (!containsMethod)
            {
                throw new Exception();
            }
            else
            {
                Console.WriteLine(methods.Length);
            }
        }
    }

    public class ImmutableList
    {
        public List<int> integers;

        public ImmutableList(List<int> integers)
        {
            this.integers = integers;
        }

        public ImmutableList ReturnImmutableListCopy()
        {
            var copy = new List<int>();

            foreach (var item in this.integers)
            {
                copy.Add(item);
            }

            return new ImmutableList(copy);
        }
    }
}