php設計模式 Command(命令模式)

<?php
/**
* 命令模式
*
* 將一個請求封裝為一個對象從而使你可用不同的請求對客戶進行參數化,對請求排除或記錄請求日誌,以及支援可取消的操作
*/
interface Command
{
public function execute();
}

class Invoker
{
private $_command = array();
public function setCommand($command) {
$this->_command[] = $command;
}

public function executeCommand()
{
foreach($this->_command as $command)
{
$command->execute();
}
}

public function removeCommand($command)
{
$key = array_search($command, $this->_command);
if($key !== false)
{
unset($this->_command[$key]);
}
}
}

class Receiver
{
private $_name = null;

public function __construct($name) {
$this->_name = $name;
}

public function action()
{
echo $this->_name." action<br/>";
}

public function action1()
{
echo $this->_name." action1<br/>";
}
}

class ConcreteCommand implements Command
{
private $_receiver;
public function __construct($receiver)
{
$this->_receiver = $receiver;
}

public function execute()
{
$this->_receiver->action();
}
}

class ConcreteCommand1 implements Command
{
private $_receiver;
public function __construct($receiver)
{
$this->_receiver = $receiver;
}

public function execute()
{
$this->_receiver->action1();
}
}

class ConcreteCommand2 implements Command
{
private $_receiver;
public function __construct($receiver)
{
$this->_receiver = $receiver;
}

public function execute()
{
$this->_receiver->action();
$this->_receiver->action1();
}
}

$objRecevier = new Receiver("No.1");
$objRecevier1 = new Receiver("No.2");
$objRecevier2 = new Receiver("No.3");

$objCommand = new ConcreteCommand($objRecevier);
$objCommand1 = new ConcreteCommand1($objRecevier);
$objCommand2 = new ConcreteCommand($objRecevier1);
$objCommand3 = new ConcreteCommand1($objRecevier1);
$objCommand4 = new ConcreteCommand2($objRecevier2); // 使用 Recevier的兩個方法

$objInvoker = new Invoker();
$objInvoker->setCommand($objCommand);
$objInvoker->setCommand($objCommand1);
$objInvoker->executeCommand();
$objInvoker->removeCommand($objCommand1);
$objInvoker->executeCommand();

$objInvoker->setCommand($objCommand2);
$objInvoker->setCommand($objCommand3);
$objInvoker->setCommand($objCommand4);
$objInvoker->executeCommand();
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