using System;
using System.Reflection;

public class AssemblyDemo
{
    public static void Main(string[] args)
    {
        int i,j;
        if (args.GetLength(0) < 1)
        {
            Console.WriteLine("usage is AssemblyDemo < library_name >");
        }
        else
        {
            Assembly assembly = Assembly.LoadFrom(args[0]);
            Type[] types = assembly.GetTypes();
            Console.WriteLine(assembly.GetName().Name + " contains the following  types");

            for (i = 0 ; i < types.GetLength(0); ++i)
            {
                Console.WriteLine("\r(" + i + ") " + types[i].Name);
            }

            i = types.Length - 1;

            Console.Write("make selection(0-" + i + "):");
            j = Convert.ToInt32(Console.ReadLine());
            Console.WriteLine();
            if (types[j].IsSubclassOf(typeof(Sport)))
            {
                ConstructorInfo ci = types[j].GetConstructor(new Type[0]);
                Sport sport = (Sport)ci.Invoke(new Object[0]);
                Console.WriteLine(sport.GetName() + " has "  + sport.GetDuration());
   
            }
            else
            {
                Console.WriteLine(types[j].Name + " is not a sub-class of Sport");
            }
        }

    }
}

             ConstructorInfo ci = types[j].GetConstructor(new Type[0]);
                Sport sport = (Sport)ci.Invoke(new Object[0]);