如何从 PHP 中使用自动加载加载的 class 捕获异常?

How to catch exception from a class loaded with autoload in PHP?

以下代码运行良好:

class D {



    public static function databaseConnected( $db_server, $db_name, $db_user, $db_password )
    {
        try {
            $newDatabaseConnection = new PDO( "mysql:host=$db_server;dbname=$db_name", $db_user, $db_password );
            $newDatabaseConnection->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
            return $newDatabaseConnection;
        }
        catch (PDOException $e) {
            //echo $e->getMessage() . "<br/>";
        }
        return null;
    }

}

echo "#HEADER#<br/>";
if ($globalConn = D::databaseConnected())
    require("content.php");
else
    echo "Cannot connect to the database!<br/>";
echo "#FOOTER#<br/>";

但是如果我用同样的方法做:

spl_autoload_register ( function ($class_name) {

    $class_name = str_replace ( "\", "/", $class_name );
    require ("{$class_name}.php");
} );

use core\system\D;

error_reporting(E_ERROR);

echo "#HEADER#<br/>";
if ($globalConn = D::databaseConnected())
    require("content.php");
else
    echo "Cannot connect to the database!<br/>";
echo "#FOOTER#<br/>";

在第一个代码中,我得到了 "Cannot connect to the database!" 错误(捕获到异常),但是在第二个代码中,我得到了连接失败导致的致命错误? (异常未捕获),我该如何解决?

(注:第二个代码中的Dclass原样位于目录\core\system\中:

<?php

namespace core\system;

use PDO;

class D {



    public static function databaseConnected( $db_server, $db_name, $db_user, $db_password )
    {
        try {
            $newDatabaseConnection = new PDO( "mysql:host=$db_server;dbname=$db_name", $db_user, $db_password );
            $newDatabaseConnection->setAttribute( PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION );
            return $newDatabaseConnection;
        }
        catch (PDOException $e) {
            //echo $e->getMessage() . "<br/>";
        }
        return null;
    }

}

?>

我正在回答我自己的问题,因为我现在明白发生了什么:问题是当脚本抛出 PDOException 时,如您所见 PDOException class执行 spl_autoload_register 时不存在,因此未捕获异常。为了解决这个问题,我将这一行放在 D:

的文件中
use PDOException;

解决方法是这样的:

<?php

namespace core\system;

use PDO;
use PDOException;

class D 
{
    public static function databaseConnected($db_server, $db_name, $db_user, $db_password)
    {
        try {
            $newDatabaseConnection = new PDO("mysql:host=$db_server;dbname=$db_name", $db_user, $db_password);
            $newDatabaseConnection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            return $newDatabaseConnection;
        }
        catch (PDOException $e) {
            //echo $e->getMessage()."<br/>";
            return null;
        }
    }
}