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HomeBackend DevelopmentPHP TutorialHow to implement the observer pattern in PHP

This article mainly introduces the observer pattern implemented in PHP, and analyzes the definition and usage of the observer pattern in PHP based on specific examples. Friends in need can refer to it

The details are as follows:

<?php
  //定义观察者调用接口
  class transfer{
    protected $_observers = array();
    //注册对象
    public function register($sub){
      $this->_observers[] = $sub;
    }
    //外部统一调用
    public function trigger(){
      if(!empty($this->_observers)){
        foreach($this->_observers as $observer){
          $observer->update();
        }
      }
    }
  }
  //观察者接口
  interface obserable{
    public function update();
  }
  //实现观察者
  class listen implements obserable{
    public function update(){
      echo &#39;now first time you need to do listen<br/>&#39;;
    }
  }
  class read implements obserable{
    public function update(){
      echo &#39;now first time you need to read<br/>&#39;;
    }
  }
  class speak implements obserable{
    public function update(){
      echo &#39;now first time you need to speak<br/>&#39;;
    }
  }
  class write implements obserable{
    public function update(){
      echo &#39;now first time you need to write<br/>&#39;;
    }
  }
  $transfer = new transfer();
  $transfer->register(new listen());
  $transfer->register(new read());
  $transfer->register(new speak());
  $transfer->register(new write());
  $transfer->trigger();

Observer modeChange the page amount The implementation code of

PHPObserver pattern

php design patternObserver PatternDetailed explanation

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