Observer pattern for Design patterns (PHP implementation)

GitHub Address: Https://github.com/ZQCard/design_pattern

/**/

(1) Subject.class.php (target Class)

<?phpnamespace Observer;classsubject{Private $state; Private $observers= [];  Public functiongetState () {return $this-State ; }     Public functionSestate ($state)    {        $this->state =$state; $this-notifyallobjects (); }     Public functionRegister (Observer$object)    {        $this->observers[] =$object; }     Public functionRemove$object)    {        foreach($this->observers as $key=$observer) {            if($observer==$object){                unset($this->observers[$key]); }        }    }     Public functionnotifyallobjects () {foreach($this->observers as $observer) {            $observer-update (); }    }}

(2) OBSERVER.CLASS.PHP (Observer abstract parent class)

<? phpnamespace Observer; Abstract class observer{    protected$subject;      Public Abstract function update ();}

(3) ObjectA.class.php (Concrete abstract Class A)

<?phpnamespace Observer;classObserveraextendsobserver{Private $myState= ' init A ';  Public function__construct (Subject$subject)    {        $this->subject =$subject; $this->subject->register ($this); }     Public functionUpdate () {$this->mystate =$this->subject->getState (); }     Public functiongetsate () {return"Observera Get state:".$this-MyState; }}

(4) ObserverB.class.php (specific observer B)

<?phpnamespace Observer;classObserverbextendsobserver{Private $myState= ' init B ';  Public function__construct (Subject$subject)    {        $this->subject =$subject; $this->subject->register ($this); }     Public functionUpdate () {$this->mystate =$this->subject->getState (); }     Public functiongetsate () {return"Observerb Get state:".$this-MyState; }}

(5) observer.php

<? phpspl_autoload_register (function ($className) {    $className  Str_replace(' \ \ ', '/',$className)    ; include $className. ". Class.php ";});  Use Observer\observera;  Use Observer\observerb;  Use observer\subject;/*

Observera Get State:init A
Observerb Get State:init B
Observera Get State:hello
Observerb Get State:hello
*/

$subject=NewSubject ();$objectA=NewObservera ($subject); $objectB=NewObserverb ($subject); Echo $objectA-getsate ();Echo' <br/> '; Echo $objectB-getsate ();Echo' <br/> '; $subject->sestate ("Hello"); Echo $objectA-getsate ();Echo' <br/> '; Echo $objectB-getsate ();Echo' <br/> ';

Observer pattern for Design patterns (PHP implementation)