C#中状态设计模式的概念示例

// 抽象状态类
public abstract class State
{
    public abstract void Open();
    public abstract void Close();
    public abstract void Run();
}

// 关闭状态类
public class ClosedState : State
{
    public override void Open()
    {
        Console.WriteLine("电梯门打开");
    }

    public override void Close()
    {
        Console.WriteLine("电梯门已经关闭");
    }

    public override void Run()
    {
        Console.WriteLine("电梯开始运行");
    }
}

// 开启状态类
public class OpenedState : State
{
    public override void Open()
    {
        Console.WriteLine("电梯门已经打开");
    }

    public override void Close()
    {
        Console.WriteLine("电梯门关闭");
    }

    public override void Run()
    {
        Console.WriteLine("电梯不能运行，门未关闭");
    }
}

// 运行状态类
public class RunningState : State
{
    public override void Open()
    {
        Console.WriteLine("电梯正在运行，不能开门");
    }

    public override void Close()
    {
        Console.WriteLine("电梯正在运行，门已关闭");
    }

    public override void Run()
    {
        Console.WriteLine("电梯正在运行中");
    }
}

// 电梯类
public class Elevator
{
    private State currentState;

    public Elevator()
    {
        // 初始状态为关闭状态
        currentState = new ClosedState();
    }

    public void SetState(State state)
    {
        currentState = state;
    }

    public void Open()
    {
        currentState.Open();
    }

    public void Close()
    {
        currentState.Close();
    }

    public void Run()
    {
        currentState.Run();
    }
}

Elevator elevator = new Elevator();
elevator.Open();  // 输出：电梯门打开

elevator.Close();  // 输出：电梯门已经关闭

elevator.Run();  // 输出：电梯开始运行

elevator.SetState(new OpenedState());
elevator.Run();  // 输出：电梯正在运行，门未关闭

elevator.Close();  // 输出：电梯门关闭