PHP design mode Command (command mode)

/**
* Command mode
*
* Encapsulates a request as an object, allowing you to parameterize clients with different requests, exclude or log requests, and support cancelable operations
*/ 
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
"; 
} 

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

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的两个方法 

$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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