未设置引用变量

Question

我创建了一个类来存储配置值。

我的配置类的代码：

class Config 
{ 
protected static $params = array(); 
protected static $instance; 

private function __construct(array $params=NULL){ 
    if(!empty($params)){ 
     self::$params = $params; 
    } 
} 

public static function init(array $params=NULL){ 
    if(!isset(self::$instance)) 
     self::$instance = new Config($params); 
} 

public static function getInstance(){ 
    return self::$instance; 
} 

public static function initialized(){ 
    return isset(self::$instance); 
} 


public static function get($name) 
{ 
    $ref = &self::$params; 
    $keys = explode('.', $name); 
    foreach ($keys as $idx => $key): 
     if (!is_array($ref) || !array_key_exists($key, $ref)) 
      return NULL; 
     $ref = &$ref[$key]; 
    endforeach; 
    return $ref;   
} 

public function delete($name){ 
    $ref = &self::$params; 
    $keys = explode('.', $name); 
    foreach ($keys as $idx => $key): 
     if (!is_array($ref) || !array_key_exists($key, $ref)) 
      return NULL; 
     $ref = &$ref[$key]; 
    endforeach; 

    unset($ref);   
} 

public function set($name, $value) { 

    $ref = &self::$params; 
    $keys = explode('.', $name); 
    foreach ($keys as $idx => $key) { 
     if (!is_array($ref)) { 
      return false; 
      throw new Exception('key "'.implode('.', array_slice($keys, 0, $idx)).'" is not an array but '.gettype($ref)); 
     } 
     if (!array_key_exists($key, $ref)) { 
      $ref[$key] = array(); 
     } 
     $ref = &$ref[$key]; 
     } 


    $ref = $value; 
    return true; 
} 

public function getAll(){ 
    return self::$params; 
} 

public function clear(){ 
    self::$params = array(); 
} 

}

配置方法采用的是点阵格式：

Config::set("test.item","testdrive"); //store in class, array["test"]["item"]="testdrive" 

但是，即时通讯试图建立一个方法来删除值，例如：

Config::delete("test.item"); 

在get和set方法中，我使用引用变量来查找正确的项目，但我不知道如何删除引用的变量。如果我使用unset($ref)，则Config::$params不受影响。

Answer 1

当你$ref = &$ref[$key];然后$ref将持有值（未REF）的$ref[$key]，所以更好地应用unset()在$ref[$key]这将取消设置它的参考，像这样：

public function delete($name){ 
    $ref = &self::$params; 
    $keys = explode('.', $name); 
    foreach ($keys as $idx => $key): 
     if (!is_array($ref) || !array_key_exists($key, $ref)) 
      return NULL; 
    endforeach; 

    unset($ref[$key]);   
}