时间：2021-07-01 10:21:17 帮助过：88人阅读
本文实例讲述了PHP观察者模式。分享给大家供大家参考，具体如下：
1.用js实现观察者模式
<!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>
<!--
我们让div对象观察select的变化，selecte变化就会通知这个2个对象，并引起这2个对象的变化，实现观察者模式。
-->
<h1>用观察者模式切换页面风格</h1>
<select>
<option value="male">男式风格</option>
<option value="female">女士风格</option>
</select>
<button onclick="t1()">观察学习区</button>
<button onclick="t2()">不观察学习区</button>
<div id="content">我是内容</div>
<div id="ad">我是广告</div>
<div id="study">学习</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);
}
}
//客户端
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 = '汽车';
}else if(ob.value == 'female'){
this.innerHTML = '减肥';
}
}
//让content观察select的变化
sel.attach('content',content);
sel.attach('ad',ad);
//新增监听study区
var study = document.getElementById('study');
study.update = function(ob){
if (ob.value == 'male') {
this.innerHTML = '学习计算机';
}else if(ob.value == 'female'){
this.innerHTML = '学习美容';
}
}
sel.attach('study',study);
function t1(){
sel.attach('study',study);
}
function t2(){
sel.detach('study');
}
</script>
</html>
2.用php实现观察模式
<?php
//php实现观察者
//php5中提供观察者observer和被观察者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();
}
}
}
//用户安全登录模块
class Safe implements SPLObserver
{
public function update(SplSubject $subject)
{
if ($subject->lognum < 3) {
echo '这是第' . $subject->lognum . '次安全登录<br>';
}else{
echo '这是第' . $subject->lognum . '次登录，异常<br>';
}
}
}
//广告模块
class Ad implements SPLObserver
{
public function update(SplSubject $subject)
{
if ($subject->hobby == 'sports') {
echo '英超开始啦<br>';
}else{
echo '好好学习<br>';
}
}
}
//实施观察
// $user = new User('sports');
$user = new User('study');
$user->attach(new Safe());
$user->attach(new Ad());
$user->login();//登录
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希望本文所述对大家PHP程序设计有所帮助。