php设计模式之命令模式使用示例_PHP
命令类:
1.命令角色:声明了一个给所有具体命令类的抽象接口。这是一个抽象角色。
2.具体命令角色:定义一个接受者和行为之间的弱耦合;实现execute方法,负责调用接受的相应操作。execute()方法通常叫做执行方法
3.客户角色:创建一个具体命令对象并确定其接受者。
4.请求者角色:负责调用命令对象执行请求,相关的方法叫做行动方法。
5.接受者角色:负责具体实施和执行一个请求。
作用:
1.抽象出待执行的动作以参数化对象。
2.在不同的时刻指定、排列和执行请求。
3.支持取消操作
4.支持修改日志
复制代码 代码如下:
//命令接口
interface Command{
public function execute();
}
//具体命令
class ConcreteCommand implements Command{
private $_receiver;
public function __construct($receiver){
$this->_receiver = $receiver;
}
public function execute(){
$this->_receiver->action();
}
}
//接受者
class Receiver{
private $_name;
public function __construct($name){
$this->_name = $name;
}
//行动方法
public function action(){
echo $this->_name.'do action .
';
}
}
//请求者
class Invoker{
private $_command;
public function __construct($command){
$this->_command = $command;
}
public function action(){
$this->_command->execute();
}
}
//客户端
class Client{
public static function main(){
$receiver = new Receiver('jaky');
$command = new ConcreteeCommand($receiver);
$invoker = new Invoker($command);
$invoker->action();
}
}
Client::main();
?>

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