使用“全局”变量的CodeIgniter计数器

Question

I am a newbie CodeIgniter developer and I must say my frustration rached to new heights when I realized I wasn't able to make work a very simple click counter. 我是CodeIgniter的新手开发人员，当我意识到无法将工作变成一个非常简单的点击计数器时，我不得不感到沮丧。 The idea is you click on a button and get the number of clicks counted. 想法是您单击一个按钮并获得计算的点击次数。 This is the view simplecounter_view: 这是视图simplecounter_view：

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');?>
<html>
    <body>  
     <?php
        echo '<form action="'. base_url().'index.php/simplecounter" method="POST">';        
        echo '<font color="blue">Click counter:' . $counter . '</font><br/><br/>';              
        echo '<input type="submit" name="myform" value="Count">';
        echo '</form>';
     ?>
    </div>
  </body>
</html>

If you click the form button it will call the SimpleCounter Controller: 如果单击表单按钮，它将调用SimpleCounter控制器：

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
class SimpleCounter extends CI_Controller { 
    public function __construct() {             
        parent::__construct();
      $this->load->helper('url');
    }
    public function index() {
        $myform=$this->input->post('myform');
        if ($myform=='Count') {
            Globals::setCounter(Globals::getCounter()+1);
        }   
        $data['counter'] = Globals::getCounter();
        $this->load->view('simplecounter_view', $data);         
    }
}

Finally, I am using a Globals class with the property $counter in order to keep its value "global" and accessible from the Controller: 最后，我将Globals类与$ counter属性一起使用，以使其值保持“全局”并可从Controller访问：

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
class Globals {
     private static $initialized=false;
     private static $counter;   

    private function __construct() {}
    private static function initialize() {
        if (self::$initialized)
            return;

        self::$counter = 0;
        self::$initialized = true;    
     }    
    public static function setCounter($n) {
        self::initialize();
        self::$counter = $n;
    }
    public static function getCounter() {
        self::initialize();
        return self::$counter;
    }
}

The code above doesn't work as I expected. 上面的代码无法正常工作。 The click counter doesn't get updated on every user click. 点击计数器不会在每次用户点击时更新。 It seems to me the Globals class gets recreated every time one of its methods is called and so $counter is reset to zero and $initialized to false. 在我看来，每次调用其方法之一时都会重新创建Globals类，因此$ counter重置为零，而$ initialized为false。

I understand there might be different approaches (like defining $counter in config.php) though I think using a separated class for keeping $counter is more elegant. 我知道可能会有不同的方法（例如在config.php中定义$ counter），尽管我认为使用单独的类来保持$ counter更为优雅。 What am I missing here? 我在这里想念什么？ Where did I get it all wrong? 我在哪里弄错了？ Your help is much appreciated. 非常感谢您的帮助。

Answer 1

Since HTTP is stateless protocol, once the http response is sent to the requesting browser all your variables get lost. 由于HTTP是无状态协议，因此一旦将HTTP响应发送到发出请求的浏览器，您的所有变量都会丢失。

In computing, a stateless protocol is a communications protocol that treats each request as an independent transaction that is unrelated to any previous request so that the communication consists of independent pairs of request and response. 在计算中，无状态协议是一种通信协议，将每个请求视为与任何先前请求均不相关的独立事务，因此通信由独立的请求和响应对组成。

You need to save the counter in a database. 您需要将计数器保存在数据库中。

使用“全局”变量的CodeIgniter计数器

问题描述

1 个解决方案

解决方案1
0 已采纳 2015-10-06 14:10:26

使用“全局”变量的CodeIgniter计数器

问题描述

1 个解决方案

解决方案1 0 已采纳 2015-10-06 14:10:26

解决方案1
0 已采纳 2015-10-06 14:10:26