设计模式--命令模式

using System;

// 定义命令接口
public interface ICommand
{
    void Execute();
}

// 具体命令类A
public class ConcreteCommandA : ICommand
{
    private Receiver receiver;

    public ConcreteCommandA(Receiver receiver)
    {
        this.receiver = receiver;
    }

    public void Execute()
    {
        receiver.Action("ConcreteCommandA");
    }
}

// 具体命令类B
public class ConcreteCommandB : ICommand
{
    private Receiver receiver;

    public ConcreteCommandB(Receiver receiver)
    {
        this.receiver = receiver;
    }

    public void Execute()
    {
        receiver.Action("ConcreteCommandB");
    }
}

// 接收者角色
public class Receiver
{
    public void Action(string commandName)
    {
        Console.WriteLine("Receiver execute " + commandName);
    }
}

// 调用者角色
public class Invoker
{
    private ICommand command;

    // 设置命令
    public void SetCommand(ICommand command)
    {
        this.command = command;
    }

    // 执行命令
    public void ExecuteCommand()
    {
        command.Execute();
    }
}

// 客户端测试
public class Client
{
    public static void Main()
    {
        Receiver receiver = new Receiver();
        ConcreteCommandA commandA = new ConcreteCommandA(receiver);
        ConcreteCommandB commandB = new ConcreteCommandB(receiver);

        Invoker invoker = new Invoker();

        invoker.SetCommand(commandA);
        invoker.ExecuteCommand();

        invoker.SetCommand(commandB);
        invoker.ExecuteCommand();
    }
}