State Pattern...??

Main.cs

using System;

namespace StatePattern
{
    class Program
    {
        static void Main(string[] args)
        {
            IState state = new StateA(); //Start state
            string target = "D"; //Target state

            //Search state
            while (state != null && target != state.StateName)
            {
                state = state.ChangeState();
            }

            //Assert
            if (state == null)
            {
                Console.WriteLine("Target state not supported.");
            }
            else
            {
                Console.WriteLine("Get state:{0}", state.StateName);
            }

            Console.ReadKey();
        }
    }
}

State.cs

using System;

namespace StatePattern
{
    interface IState
    {
        string StateName { get; }

        IState ChangeState();
    }

    class StateA : IState
    {
        public StateA()
        { }

        public string StateName { get { return "A"; } }

        public IState ChangeState()
        {
            Console.WriteLine("Change state A to B.");
            return new StateB();
        }

    }

    class StateB : IState
    {
        public StateB()
        { }

        public string StateName { get { return "B"; } }

        public IState ChangeState()
        {
            Console.WriteLine("Change state B to C.");
            return new StateC();
        }

    }

    class StateC : IState
    {
        public StateC()
        { }

        public string StateName { get { return "C"; } }

        public IState ChangeState()
        {
            Console.WriteLine("StateC is end of state.");
            return null;
        }

    }
}