<?PHP
    namespace App\Database;
    use Symfony\Component\Yaml\Yaml;

    class Database{
        private static $connection = null;

        private function __construct( $host,$base,$user,$pass ){
            try{
                self::$connection = new PDO("MysqL:host=$host;dbname=$base",$pass);
            }catch(PDOException $e){
                die($e->getMessage());
            }
        }

        public static function get(){
            if( self::$connection !== null ){
                return self::$connection;
            }
            $yaml = Yaml::parse(file_get_contents(realpath('./app') . '/database.yml'));
            self::$connection = new Database( $yaml['host'],$yaml['base'],$yaml['user'],$yaml['pass'] );
        }
    }

使用作曲家,我自动加载这个类：

{
    "autoload" : {
        "classmap" : [
            "app/libraries","app/db"
        ]
    }
}

其中生成一个autoload_classmap.PHP,如：

return array(
    'App\\Database\\Database' => $baseDir . '/app/db/MysqL/database.PHP','App\\Libraries\\Parser' => $baseDir . '/app/libraries/Parser.PHP',);

现在,一切正常,我总是会遇到与PDO有关的错误：

Fatal error: Class 'App\Database\PDO' not found in /var/www/my_application/app/db/MysqL/database.PHP on line 24

我认为问题来自于命名空间,因为当我将类放入索引页面时,我没有任何错误. PDO已安装并工作.