设计模式专题（十九） ——命令模式

//1：命令通用虚类
abstract class Command{
         protected$receiver;
         publicfunction __construct(Receiver $receiver){
                   $this->receiver= $receiver;
         }
         publicfunction execute(){}
}

//2：具体命令执行类
class ConcreteCommand extends Command{
         function__construct(Receiver $receiver){
                   parent::__construct($receiver);
         }
         publicfunction execute(){
                   $this->receiver->action();
         }
}

//3：发动命令类
class Invoker{
         private$command;
         publicfunction __construct(Command $command){
                   $this->command= $command;
         }
         publicfunction setCommand(Command $command){
                   $this->command= $command;
         }
         publicfunction executeCommand(){
                   $this->command->execute();
         }
}

//4：命令接收者类
class Receiver{
         publicfunction action(){
                   echo'执行请求';
         }
}

$r = new Receiver();
$c = new ConcreteCommand($r);
$i = new Invoker($c);
$i->executeCommand();