abstract class Command public abstract void Execute public abstract vo

abstract class Command
{
    public abstract void Execute();
    public abstract void Undo();
}
// конкретная команда
class ConcreteCommand : Command
{
    Receiver receiver;
    public ConcreteCommand(Receiver r)
    {
        receiver = r;
    }
    public override void Execute()
    {
        receiver.Operation();
    }
 
    public override void Undo()
    {}
}
 
// получатель команды
class Receiver
{
    public void Operation()
    { }
}
// инициатор команды
class Invoker
{
    Command command;
    public void SetCommand(Command c)
    {
        command = c;
    }
    public void Run()
    {
        command.Execute();
    }
    public void Cancel()
    {
        command.Undo();
    }
}
class Client
{  
    void Main()
    {
        Invoker invoker = new Invoker();
        Receiver receiver = new Receiver();
        ConcreteCommand command=new ConcreteCommand(receiver);
        invoker.SetCommand(command);
        invoker.Run();
    }
}