php - MySQLI 扩展和原生错误处理

Question

我正在尝试扩展 PHP5 MySQLi 库

class mysqli_ls extends mysqli

我扩展该类的原因是添加默认情况下不包含的我需要的功能和特性。对于我创建的函数，我想以与处理任何 native 函数完全相同的方式处理错误。

我希望使用该类的人不必确定这些功能是原生的还是定制的。

正常功能

if ($_mysqli->query($sql) === false) die($_mysqli->error);

所需的定制功能示例

if ($_mysqli->run_config() === false) 死($_mysqli->error);

类(class)

在我的扩展 mysqli 的类 mysqli_ls 中，我有以下函数，我希望它们能在父 mysqli 类中设置错误消息..

   public function run_config()
   {
      // Open Debug FH
      if ($this->config['debug_log'] === TRUE)
      {
         if ($this->fh_debug = fopen($this->config['debug_log_path'], 'a') === FALSE) 
         {
            $this->handle_error('Could not open Debug file handle','200',__METHOD__);
            return $this->E_ERROR;
         }
      }
  }



private function handle_error($errormsg,$errorno,$method)
   {
      $this->errorno = $errorno;
      $this->error   = $errormsg;

      if ($this->config['debug_log'] === TRUE)
      {
         $msg = "($errorno) $errormsg";                              
         $this->write_log('error', $method, $msg);
      }

      return $this->E_OK;
   }

我已经尝试了上面的方法，它出错了:
PHP fatal error :mysqli_ls::handle_error(): 无法写入属性

以及导致语法错误的静态调用语法，如下所示:

parent::error
parent::errorno 

我希望该类的用户无缝地拥有默认的 MySQLI 功能和扩展功能，而不必使用不同的方法来识别错误。

提前感谢您提供的任何建议或意见。

编辑:添加全类

class mysqli_ls extends mysqli
{
   private $config = array
   (
      'config_load'     => FALSE,
      'config_path'     => 'mysqli_ls.database.ini',

      'debug_log'       => FALSE,
      'debug_log_path'  => '/tmp/mysqli_ls.debug.log',

      'query_log'       => FALSE,
      'query_log_path'  => '/tmp/mysqli_ls.debug.log',

      'log_date_format' => 'Y-m-d H:i:s'
   );

   // Expected fields for the autoload file
   private $db_fields = array('hostname','username','password','database','port');

   // File Handles
   private $fh_debug  = FALSE;
   private $fh_query  = FALSE;
   private $fh_config = FALSE;

   // Return presets
   private $E_OK    = TRUE;
   private $E_ERROR = FALSE;

   // Existing database connections
   private $db_existing = array();

   public $error;
   public $errorno;

   ## ----------
   public function __construct()
   {
      if (!function_exists('mysqli_connect')) $this->handle_error('MySQLI is not installed','100');
   }

   ## ----------
   public function run_config()
   {
      // Testing error handling
      $this->handle_error('Could not open Debug file handle','200',__METHOD__);

      // Open Debug FH
      if ($this->config['debug_log'] === TRUE)
      {
         if ($this->fh_debug = fopen($this->config['debug_log_path'], 'a') === FALSE) 
         {
            $this->handle_error('Could not open Debug file handle','200',__METHOD__);
            return $this->E_ERROR;
         }
      }

      // Open Query FH
      if ($this->config['query_log'] === TRUE) 
      {
         if ($this->fh_query = fopen($this->config['query_log_path'], 'a') === FALSE)
         {
            $this->handle_error('Could not open Debug file handle','210');            
            return $this->E_ERROR;
         }
      }

      // Load database INI file
      if ($this->config['config_load'] === TRUE)
      {
         if ( ($this->db_existing = parse_ini_file($this->config['config_path'], TRUE)) === FALSE )
         {
            $this->handle_error('Could not parse the database ini file','220'); 
            return $this->E_ERROR;
         }
      }

      // Check for format of the loaded ini file
      foreach($this->db_existing as $name => $row)
      {
         foreach($this->db_fields as $field)
         {
            if ( !isset($row[$field]) ) 
            {
               $this->handle_error("Missing field ($field) in the config array for element ($name)",'230'); 
               return $this->E_ERROR;
            }
         } // END foreach
      } // END foreach

      return $this->E_OK;
   }

   ## ----------
   public function set_config($key, $value)
   {
      if ( !isset($this->config[$key]) ) 
      {
         $this->handle_error('Configuration variable ($key) does not exist','300');
         return $this->E_ERROR;
      }

      $this->config[$key] = $value;
      return $this->E_OK;
   }

   ## ----------
   public function get_config()
   {
      return array_merge($this->config, $this->db_existing);
   }

   ## ----------
   private function write_log($type,$method,$msg)
   {
      $msg = date($this->config['log_date_format']) ."\t". $type ."\t". $method ."\t". $msg ."\n";

      switch($type)
      {
         case 'error':
            fwrite($this->fh_debug, $msg);
         break;

         case 'debug':
            fwrite($this->fh_debug, $msg);
         break;

         case 'query':
            fwrite($this->fh_query, $msg);
         break;

         default:
            return $this->E_ERROR;
         break;      
      }
   }

   ## ----------
   private function handle_error($errormsg,$errorno,$method)
   {
      $this->errorno = $errorno;
      $this->error   = $errormsg;

      if ($this->config['debug_log'] === TRUE)
      {
         $msg = "($errorno) $errormsg";                              
         $this->write_log('error', $method, $msg);
      }

      return $this->E_OK;
   }

   ## ----------
   ## ----------
   ## ----------
   ## ----------      

} // END Class

调用类的测试脚本

#!/usr/bin/php
<?php

require('mysqli_ls.class.php');

try
{
   $_mysqli = new mysqli_ls;
}
catch (Exception $e)
{
  print "\n\n". $e->getMessage() ."\n\n";
   print_r($e);
}

$_mysqli->set_config('debug_log',TRUE);
$_mysqli->set_config('query_log',TRUE);
$_mysqli->set_config('config_load',TRUE);

$_mysqli->run_config();
print_r($_mysqli->get_config());

?>

编辑:所以看起来 MySQLi 类中的错误变量可能是只读的。还有其他方法可以解决这个问题吗？我想也许有我自己的错误函数来检查父类和我自己的变量。

Answer 1

使用 __get魔术函数，您可以做一些检查是否设置了父级的错误变量。像这样的东西:

class mysqli_ls extends mysqli{
  public $error;
  public $errorno;
  public $connect_error;
  public $connect_errorno;

  function __get($key){
    if(in_array($key, array('error', 'errorno', 'connect_error', 'connect_errorno'))){
      $parentValue = parent::$key;
      if(empty($parentValue)){
        return $this->$key;
      }
      return $parentValue;
    }
  }
}

小测试脚本:

<?php
$test = @new mysqli2('localhost', 'badlogin', 'whatisapassword', 'anonexistentdb');
echo 'test : '.$test->connect_error;