在PHP中的扩展类中使用父变量

Question

我有2个课程,主要和扩展.我需要在扩展类中使用主变量.

<?php
class Main {
  public $vars = array();
}

$main = new Main;

$main->vars['key'] = 'value';

class Extended extends Main { }

$other = new Extended;

var_dump($other->vars);

?>

我能做谁？

无效例如:

<?php
class Extended extends Main {
  function __construct ($main) {
    foreach ($main as $k => $v) {
      $this->$k = $v;
    }
  }
}
?>

我需要一些更透明,更有效的解决方案:)

Answer 1

使用简单的构造函数很容易实现

<?php

class One {

    public static $string = "HELLO";

}

class Two extends One {

    function __construct()
    {
        parent::$string = "WORLD";
        $this->string = parent::$string;
    }

}

$class = new Two;
echo $class->string; // WORLD

?>

Answer 2

编辑：这可以通过控制反转（IoC）和依赖注入（DI）更好地解决。如果您使用自己的框架或没有依赖注入容器的框架，请尝试League/Container

下面的答案作为愚蠢答案的历史。

我认为正确的方法。

<?php
class Config {
    protected $_vars = array();

    protected static $_instance;

    private function __construct() {}

    public static function getInstance()
    {
        if (!isset(self::$_instance)) {
            self::$_instance = new self();
        }
        return self::$_instance;
    }

    public function &__get($name) {
        return $this->_vars[$name];
    }

    public function __set ($name, $value) {
        $this->_vars[$name] = $value;
    }
}

$config = Config::getInstance();
$config->db = array('localhost', 'root', '');
$config->templates = array(
    'main' => 'main',
    'news' => 'news_list'
);

class DB {
    public $db;

    public function __construct($db)
    {
        $this->db = $db;
    }

    public function connect()
    {
        mysql_connect($this->db[0], $this->db[1], $this->db[2]);
    }
}

$config = Config::getInstance();
$db = new DB($config->db);
$db->connect();

class Templates {
    public $templates;

    public function __construct($templates)
    {
        $this->templates = $templates;
    }

    public function load ($where) {
        return $this->templates[$where];
    }
}

$config = Config::getInstance();
$templates = new Templates($config->templates);
echo $templates->load('main') . "\n";