设计模式之状态模式

public interface IState {

   void WriteName(StateContext stateContext, string name);

}

public class StateA : IState {
   
   public void WriteName(StateContext stateContext, string name) {
      Console.WriteLine(name.ToLower());
      stateContext.SetState(new StateB());
   }
}

public class StateB : IState {

   private int _count;

   public void WriteName(StateContext stateContext, string name) {
      Console.WriteLine(name.ToUpper());
      if (++this._count > 1) {
         stateContext.SetState(new StateA());
      }
   }
}

public class StateContext {
   
   private IState _state;

   public StateContext() {
      this._state = new StateA();
   }

   public void SetState(IState state) {
      this._state = state;
   }

   public void WriteName(string name) {
      this._state.WriteName(this, name);
   }
}

class Client {

   static void Main(string[] args) {
      var sc = new StateContext();
      sc.WriteName("Monday");
      sc.WriteName("Tuesday");
      sc.WriteName("Wednesday");
      sc.WriteName("Thursday");
      sc.WriteName("Saturday");
      sc.WriteName("Sunday");

      Console.ReadKey();
   }
}