本文實例講述了PHP設計模式之觀察者模式定義與用法。分享給大家供大家參考，具體如下：
<?php
/**
* Interface Observable
* define a observable interface
* @author jichao.wang
*/
interface Observable
{
function attach(Observer $observer);
function detach(Observer $observer);
function notify();
}
/**
* Class Login
* @author jichao.wang
*/
class Login implements Observable
{
private $observers;
public $status;
public $ip;
const LOGIN_ACCESS = 1;
const LOGIN_WRONG_PASS = 2;
const LOGIN_USER_UNKNOWN = 3;
function __construct()
{
$this->observers = array();
}
/**
* @param Observer $observer
* @author jichao.wang
* attach a observer
*/
function attach(Observer $observer)
{
$this->observers[] = $observer;
}
/**
* @param Observer $observer
* @author jichao.wang
* detach a observer
*/
function detach(Observer $observer)
{
$newObservers = array();
foreach ($this->observers as $key => $obs) {
if ($obs !== $observer) {
$newObservers[] = $obs;
}
}
$this->observers = $newObservers;
}
/**
* @author jichao.wang
* handle observer notify
*/
function notify()
{
foreach ($this->observers as $obs) {
$obs->update($this);
}
}
/**
* @author jichao.wang
* 執行登陸
*/
function handleLogin()
{
$ip = rand(1,100);
switch (rand(1, 3)) {
case 1:
$this->setStatus(self::LOGIN_ACCESS, $ip);
$ret = true;
break;
case 2:
$this->setStatus(self::LOGIN_WRONG_PASS, $ip);
$ret = false;
break;
case 3:
$this->setStatus(self::LOGIN_USER_UNKNOWN, $ip);
$ret = false;
break;
}
/**
* handle event
*/
$this->notify();
return $ret;
}
/**
* @param $status
* @author jichao.wang
* set login status
*/
function setStatus($status,$ip)
{
$this->status = $status;
$this->ip = $ip;
}
/**
* @return mixed
* @author jichao.wang
* get login status
*/
function getStatus()
{
return $this->status;
}
}
/**
* Interface Observer
* @author jichao.wang
*/
interface Observer {
function update(Observable $observable);
}
/**
* Class EmailObserver
* @author jichao.wang
*/
class EmailObserver implements Observer {
function update (Observable $observable) {
$status = $observable->getStatus();
if($status == Login::LOGIN_ACCESS){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸成功!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸成功!'.'------------------';
}
if($status == Login::LOGIN_WRONG_PASS){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸失敗，密碼錯誤!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸失敗，密碼錯誤!'.'------------------';
}
if($status == Login::LOGIN_USER_UNKNOWN){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸失敗，無此用戶!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸失敗，無此用戶!'.'------------------';
}
}
}
/**
* Class PhoneObserver
* @author jichao.wang
*/
class PhoneObserver implements Observer {
function update (Observable $observable) {
$status = $observable->getStatus();
if($status == Login::LOGIN_ACCESS){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸成功!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸成功!'.'------------------';
}
if($status == Login::LOGIN_WRONG_PASS){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸失敗，密碼錯誤!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸失敗，密碼錯誤!'.'------------------';
}
if($status == Login::LOGIN_USER_UNKNOWN){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸失敗，無此用戶!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸失敗，無此用戶!'.'------------------';
}
}
}
class AbcObserver implements Observer {
function update (Observable $observable) {
$status = $observable->getStatus();
if($status == Login::LOGIN_ACCESS){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸成功!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸成功!'.'------------------';
}
if($status == Login::LOGIN_WRONG_PASS){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸失敗，密碼錯誤!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸失敗，密碼錯誤!'.'------------------';
}
if($status == Login::LOGIN_USER_UNKNOWN){
// $this->sendMail('用戶ip:'.$observable->ip.'登陸失敗，無此用戶!');
echo __CLASS__.'用戶ip:'.$observable->ip.'登陸失敗，無此用戶!'.'------------------';
}
}
}
//實例化登陸信息
$login = new Login();
//實現發郵件觀察者
$login->attach(new EmailObserver());
//實現發驗證碼觀察者
$login->attach(new PhoneObserver());
//實現其他觀察者
$login->attach(new AbcObserver());
//開始登陸
$login->handleLogin();
?>
運行結果：
EmailObserver用戶ip:41登陸失敗，無此用戶!------------------PhoneObserver用戶ip:41登陸失敗，無此用戶!------------------AbcObserver用戶ip:41登陸失敗，無此用戶!------------------
希望本文所述對大家PHP程序設計有所幫助。
