PHP5+標准函數庫觀察者之實現

PHP5+標准函數庫觀察者之實現

PHP的觀察者設計模式實現相對簡單，但是PHP5+版本中已經有標准庫類庫支持，我們只需簡單繼承並實現就可以了。

觀察者：實現標准接口類庫SplSubject。一個注冊方法：attach，一個取消注冊方法：detach。一個通知方法：nofity。

observers =array();
	 }

	 public function attach(SplObserver $observer){
		$this->observers[] = $observer;
	 }

	 public function detach(SplObserver $observer){
		if($idx = array_search($observer, $this->observers,true)) {
			unset($this->observers[$idx]);
		}
	 }
	 
    /**
	 *
	 * Notify observers one by one (main entry)
	 *
	 * @param none
	 * @return none
	 */
	 public function notify(){
		foreach($this->observers as $observer){
			$observer->update($this);
		}
	 }

	 public function setValue($value){
		$this->value = $value;
		//$this->notify();
	 }

	 public function getValue(){
		 return $this->value;
	 }
}

getValue();
	 }
}

getValue();
	 }
}

attach(new TSPLObserver());
$observer1 = new TSPLObserver1();
$subject->attach($observer1);
//$subject->attach(new TSPLObserver2());
//$subject->detach($observer1);

$subject->notify();

exit();

>php basic.php
The new state of subject

The new state of subject one