find has an interface class

command.cs

//System.Reflection 

 
    public class Invoker
    {
        private readonly List<object> _mCommand;

        private const BindingFlags Flags = BindingFlags.Public | BindingFlags.DeclaredOnly | BindingFlags.Instance;

        public Invoker()
        {
            _mCommand = (from type in Assembly.GetExecutingAssembly().GetTypes()
                         where type.IsClass && type.GetInterfaces().Contains(typeof(IExeCute))
                         select Activator.CreateInstance(type)).ToList();

        }


        [Fact]
        public static void DoTestRefTest()
        {
            var o = new Invoker();
            o.GetCommand(CommandEnum.File).Execute();

        }


        private IExeCute GetCommand(CommandEnum command)
        {
            var single = _mCommand.Single(o => o.GetType().
                                                   GetFields(Flags)
                                                   .Any(info => (CommandEnum)info.GetValue(o) == command));
           
            if (single == null) throw new ArgumentNullException("command");


            return single as IExeCute;
        }
    }