CSharp: Command Pattern in donet core 3

  /// <summary>
    ///  Receiver Class
    /// 命令模式 Command Pattern 亦称： 动作、事务、Action、Transaction、Command
    /// geovindu,Geovin Du eidt
    /// </summary>  
    public class Game
    {
        /// <summary>
        /// 游戏名称
        /// </summary>
        string gameName;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="name">输入名称</param>
        public Game(string name)
        {
            this.gameName = name;
        }
        /// <summary>
        /// 开始
        /// </summary>
        public void Start()
        {
            Console.WriteLine($"{gameName} 开始.");
        }
        /// <summary>
        /// 显示比分
        /// </summary>
        public void DisplayScore()
        {
            Console.WriteLine("比分随时在变化.");
        }
        /// <summary>
        /// 完成
        /// </summary>
        public void Finish()
        {
            Console.WriteLine($"---游戏： {gameName} 完成结束.---");
        }

    }
    /// <summary>
    /// The command interface
    /// </summary>
    public interface ICommand
    {
        //To execute a command
        /// <summary>
        /// 执行
        /// </summary>
        void Execute();
        //To undo last command execution
        /// <summary>
        /// 结束
        /// </summary>
        void Undo();

    }
    /// <summary>
    /// GameStartCommand
    /// 开始命令
    /// </summary>
    public class GameStartCommand : ICommand
    {
        /// <summary>
        /// 游戏
        /// </summary>
        private Game game;
        /// <summary>
        /// 开始运行
        /// </summary>
        /// <param name="game"></param>
        public GameStartCommand(Game game)
        {
            this.game = game;
        }
        /// <summary>
        /// 执行
        /// </summary>
        public void Execute()
        {

            game.Start();

            game.DisplayScore();
        }
        /// <summary>
        /// 卸载
        /// </summary>
        public void Undo()
        {
            Console.WriteLine("取消起动命令.");
            game.Finish();
        }
    }
    /// <summary>
    /// GameStopCommand
    /// 停止游戏命令
    /// </summary>

    public class GameStopCommand : ICommand
    {
        /// <summary>
        /// 
        /// </summary>
        private Game game;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="game"></param>
        public GameStopCommand(Game game)
        {
            this.game = game;
        }
        /// <summary>
        /// 
        /// </summary>
        public void Execute()
        {
            Console.WriteLine("完成游戏.");
            game.Finish();
        }
        /// <summary>
        /// 
        /// </summary>
        public void Undo()
        {
            Console.WriteLine("取消停止命令.");
            game.Start();
            game.DisplayScore();
        }
    }

    /// <summary>
    /// Invoker class
    /// 遥控
    /// </summary>
    public class RemoteControl
    {
        /// <summary>
        /// 
        /// </summary>
        ICommand commandToBePerformed, lastCommandPerformed;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="command"></param>
        public void SetCommand(ICommand command)
        {
            this.commandToBePerformed = command;
        }
        /// <summary>
        /// 
        /// </summary>
        public void ExecuteCommand()
        {
            commandToBePerformed.Execute();
            lastCommandPerformed = commandToBePerformed;
        }
        /// <summary>
        /// 
        /// </summary>
        public void UndoCommand()
        {
            //Undo the last command executed
            lastCommandPerformed.Undo();
        }
    }

   /// <summary>
    /// 命令模式 Command Pattern 亦称： 动作、事务、Action、Transaction、Command
    /// geovindu,Geovin Du eidt
    /// </summary>
    public class BankAccount
        {
            public int Balance;
        }

    /// <summary>
    /// 
    /// </summary>
    public class FunctionalCommand
    {

        /// <summary>
        /// 
        /// </summary>
        /// <param name="account"></param>
        /// <param name="amount"></param>
        public void Deposit(BankAccount account, int amount)
        {
            account.Balance += amount;
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="account"></param>
        /// <param name="amount"></param>
        public void Withdraw(BankAccount account, int amount)
        {
            if (account.Balance >= amount)
            {
                account.Balance -= amount;
                Console.WriteLine($"{account.Balance}:{amount}");
            }
            else
            {
                account.Balance = amount;
                Console.WriteLine($"{account.Balance}:{amount}");
            }
               
        }
        /// <summary>
        /// 
        /// </summary>
       public FunctionalCommand()
        {
            var ba = new BankAccount();
            var commands = new List<Action>();

            commands.Add(() => Deposit(ba, 100));
            commands.Add(() => Withdraw(ba, 100));

            commands.ForEach(c => c());
        }


    }

   /// <summary>
    /// 命令模式 Command Pattern 亦称： 动作、事务、Action、Transaction、Command
    /// geovindu,Geovin Du eidt
    /// </summary>
    public class BankAccount
    {

        /// <summary>
        /// 
        /// </summary>
        private int balance;
        /// <summary>
        /// 
        /// </summary>
        private readonly int overdraftLimit = -500;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="balance"></param>
        public BankAccount(int balance = 0)
        {
            this.balance = balance;
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="amount"></param>
        public void Deposit(int amount)
        {
            balance += amount;
            Console.WriteLine($"Deposited ${amount}, balance is now {balance}");
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="amount"></param>
        /// <returns></returns>
        public bool Withdraw(int amount)
        {
            if (balance - amount >= overdraftLimit)
            {
                balance -= amount;
                Console.WriteLine($"Withdrew ${amount}, balance is now {balance}");
                return true;
            }
            return false;
        }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            return $"{nameof(balance)}: {balance}";
        }
    }
    /// <summary>
    /// 
    /// </summary>
    public interface ICommand
    {
        void Call();
        void Undo();
        bool Success { get; set; }
    }
    /// <summary>
    /// 
    /// </summary>
    public class BankAccountCommand : ICommand
    {
        /// <summary>
        /// 
        /// </summary>
        private readonly BankAccount account;
        /// <summary>
        /// 
        /// </summary>
        public enum Action
        {
            Deposit, Withdraw
        }
        /// <summary>
        /// 
        /// </summary>
        private readonly Action action;
        /// <summary>
        /// 
        /// </summary>
        private readonly int amount;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="account"></param>
        /// <param name="action"></param>
        /// <param name="amount"></param>
        public BankAccountCommand(BankAccount account, Action action, int amount)
        {
            this.account = account;
            this.action = action;
            this.amount = amount;
        }
        /// <summary>
        /// 
        /// </summary>
        /// <exception cref="ArgumentOutOfRangeException"></exception>
        public void Call()
        {
            switch (action)
            {
                case Action.Deposit:
                    account.Deposit(amount);
                    Success = true;
                    break;
                case Action.Withdraw:
                    Success = account.Withdraw(amount);
                    break;
                default:
                    throw new ArgumentOutOfRangeException();
            }
        }
        /// <summary>
        /// 
        /// </summary>
        /// <exception cref="ArgumentOutOfRangeException"></exception>
        public void Undo()
        {
            if (!Success) return;
            switch (action)
            {
                case Action.Deposit:
                    account.Withdraw(amount);
                    break;
                case Action.Withdraw:
                    account.Deposit(amount);
                    break;
                default:
                    throw new ArgumentOutOfRangeException();
            }
        }
        /// <summary>
        /// 
        /// </summary>
        public bool Success { get; set; }
    }
    /// <summary>
    /// 
    /// </summary>
    public class CompositeBankAccountCommand        
      : List<BankAccountCommand>, ICommand
    {
        /// <summary>
        /// 
        /// </summary>
        public CompositeBankAccountCommand()
        {
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="collection"></param>
        public CompositeBankAccountCommand(
          [NotNull] IEnumerable<BankAccountCommand> collection) : base(collection)
        {
        }
        /// <summary>
        /// 
        /// </summary>
        public virtual void Call()
        {
            Success = true;
            ForEach(cmd =>
            {
                cmd.Call();
                Success &= cmd.Success;
            });
        }
        /// <summary>
        /// 
        /// </summary>
        public virtual void Undo()
        {
            foreach (var cmd in
              ((IEnumerable<BankAccountCommand>)this).Reverse())
            {
                cmd.Undo();
            }
        }
        /// <summary>
        /// 
        /// </summary>
        public bool Success { get; set; }
    }
    /// <summary>
    /// 
    /// </summary>
    public class MoneyTransferCommand : CompositeBankAccountCommand
    {

        /// <summary>
        /// 
        /// </summary>
        /// <param name="from"></param>
        /// <param name="to"></param>
        /// <param name="amount"></param>
        public MoneyTransferCommand(BankAccount from,
          BankAccount to, int amount)
        {
            AddRange(new[]
            {
        new BankAccountCommand(from,
          BankAccountCommand.Action.Withdraw, amount),
        new BankAccountCommand(to,
          BankAccountCommand.Action.Deposit, amount),
      });
        }
        /// <summary>
        /// 
        /// </summary>
        public override void Call()
        {
            BankAccountCommand last = null;
            foreach (var cmd in this)
            {
                if (last == null || last.Success)
                {
                    cmd.Call();
                    last = cmd;
                }
                else
                {
                    cmd.Undo();
                    break;
                }
            }
        }
    }

调用：

            //命令模式
            Console.WriteLine("***命令模式 Command Pattern Demonstration***\n");

            /*Client holds both the Invoker and Command Objects*/
            RemoteControl invoker = new RemoteControl();

            Game gameName = new Game("高尔夫游戏");
            //Command to start the game
            GameStartCommand gameStartCommand = new GameStartCommand(gameName);
            //Command to stop the game
            GameStopCommand gameStopCommand = new GameStopCommand(gameName);

            Console.WriteLine("**开始游戏并立即执行撤销.**");
            invoker.SetCommand(gameStartCommand);
            invoker.ExecuteCommand();
            //Performing undo operation
            Console.WriteLine("\n现在撤消上一个命令");
            invoker.UndoCommand();           

            Console.WriteLine("\n**重新开始游戏。然后停止它，撤销停止操作.**");
            invoker.SetCommand(gameStartCommand);
            invoker.ExecuteCommand();
            //Stop command to finish the game
            //执行停止操作
            invoker.SetCommand(gameStopCommand);
            invoker.ExecuteCommand();
            //Performing undo operation
            Console.WriteLine("\n现在撤消上一个命令.");
            invoker.UndoCommand();

            Console.WriteLine();
            //
            var b =new  BankAccount();
            var c=new FunctionalCommand();
            c.Withdraw(b,2);

            Console.WriteLine();
            //
            // composite
            var ba = new GevoinDuCommandPattern.BankAccount();
            var cmdDeposit = new GevoinDuCommandPattern.BankAccountCommand(ba,
               GevoinDuCommandPattern.BankAccountCommand.Action.Deposit, 100);
            var cmdWithdraw = new GevoinDuCommandPattern.BankAccountCommand(ba,
               GevoinDuCommandPattern.BankAccountCommand.Action.Withdraw, 1000);
            var composite = new GevoinDuCommandPattern.CompositeBankAccountCommand(new[]{
        cmdDeposit, cmdWithdraw
      });

            composite.Call();
            Console.WriteLine(ba);

            composite.Undo();
            Console.WriteLine(ba);


            // money transfer
            var from = new GevoinDuCommandPattern.BankAccount();
            from.Deposit(100);
            var toGeovinDu = new GevoinDuCommandPattern.BankAccount();

            var mtc = new GevoinDuCommandPattern.MoneyTransferCommand(from, toGeovinDu, 1000);
            mtc.Call();

            Console.WriteLine(from);
            Console.WriteLine(toGeovinDu);

            mtc.Undo();

            Console.WriteLine(from);
            Console.WriteLine(toGeovinDu);

输出：

***命令模式 Command Pattern Demonstration***

**开始游戏并立即执行撤销.**
高尔夫游戏 开始.
比分随时在变化.

现在撤消上一个命令
取消起动命令.
---游戏： 高尔夫游戏 完成结束.---

**重新开始游戏。然后停止它，撤销停止操作.**
高尔夫游戏 开始.
比分随时在变化.
完成游戏.
---游戏： 高尔夫游戏 完成结束.---

现在撤消上一个命令.
取消停止命令.
高尔夫游戏 开始.
比分随时在变化.

0:100
2:2

Deposited $100, balance is now 100
balance: 100
Withdrew $100, balance is now 0
balance: 0
Deposited $100, balance is now 100
balance: 100
balance: 0
balance: 100
balance: 0
t