本文實例講述了PHP觀察者模式。分享給大家供大家參考，具體如下：
1.用js實現觀察者模式
<!DOCTYPE html><html><head> <title></title> <style type="text/css"> div{width: 100px;height: 100px;border: 1px #999 solid;margin-bottom: 5px;} </style></head><body><!--我們讓div對象觀察select的變化，selecte變化就會通知這個2個對象，并引起這2個對象的變化，實現觀察者模式。 --> <h1>用觀察者模式切換頁面風格</h1> <select> <option value="male">男式風格</option> <option value="female">女士風格</option> </select> <button onclick="t1()">觀察學習區</button> <button onclick="t2()">不觀察學習區</button> <div id="content">我是內容</div> <div id="ad">我是廣告</div> <div id="study">學習</div></body><script type="text/javascript"> var sel = document.getElementsByTagName('select')[0]; sel.observers = {}; sel.attach = function(key,obj){ this.observers[key] = obj; } sel.detach = function(key){ delete this.observers[key]; } sel.onchange = sel.notify = function(){ for(var key in this.observers){ this.observers[key].update(this); } } //客戶端 var content = document.getElementById('content'); var ad = document.getElementById('ad'); content.update = function(ob){ if (ob.value == 'male') { this.style.backgroundColor = 'gray'; }else if(ob.value == 'female'){ this.style.backgroundColor = 'pink'; } } ad.update = function(ob){ if (ob.value == 'male') { this.innerHTML = '汽車'; }else if(ob.value == 'female'){ this.innerHTML = '減肥'; } } //讓content觀察select的變化 sel.attach('content',content); sel.attach('ad',ad); //新增監聽study區 var study = document.getElementById('study'); study.update = function(ob){ if (ob.value == 'male') { this.innerHTML = '學習計算機'; }else if(ob.value == 'female'){ this.innerHTML = '學習美容'; } } sel.attach('study',study); function t1(){ sel.attach('study',study); } function t2(){ sel.detach('study'); }</script></html>2.用php實現觀察模式
<?php//php實現觀察者//php5中提供觀察者observer和被觀察者subject的接口class User implements SplSubject{ public $lognum; public $hobby; protected $observers = null; public function __construct($hobby) { $this->lognum = rand(1,10); $this->hobby = $hobby; $this->observers = new SplObjectStorage(); } public function login() { //操作session等 $this->notify(); } public function attach(SPLObserver $observer) { $this->observers->attach($observer); } public function detach(SPLObserver $observer) { $this->observers->detach($observer); } public function notify() { $this->observers->rewind(); while ($this->observers->valid()) { $observer = $this->observers->current(); $observer->update($this); $this->observers->next(); } }}//用戶安全登錄模塊class Safe implements SPLObserver{ public function update(SplSubject $subject) { if ($subject->lognum < 3) { echo '這是第' . $subject->lognum . '次安全登錄<br>'; }else{ echo '這是第' . $subject->lognum . '次登錄，異常<br>'; } }}//廣告模塊class Ad implements SPLObserver{ public function update(SplSubject $subject) { if ($subject->hobby == 'sports') { echo '英超開始啦<br>'; }else{ echo '好好學習<br>'; } }}//實施觀察// $user = new User('sports');$user = new User('study');$user->attach(new Safe());$user->attach(new Ad());$user->login();//登錄
希望本文所述對大家PHP程序設計有所幫助。
新聞熱點
疑難解答
圖片精選
