static void Main(string[] args)
        {
            Context context = new Context(new ConcreteStrategyA());
            context.Execute();

            context.Strategy = new ConcreteStrategyB();
            context.Execute();

            Console.Read();
        }
        public void BasicBaseStrategyTest()
        {
            var con = new Context(new ConcreteStrategyA());
            Assert.AreEqual(con.Execute(), "A");

            con = new Context(new ConcreteStrategyB());
            Assert.AreEqual(con.Execute(), "B");
        }