PHP pdo单例模式连接数据库_newmiracle学习天地

PHP pdo单例模式连接数据库
  ';
        if ( self::$pdo == null )
        {
            $host = '115.29.223.160';
            $user = 'zhangwei';
            $pwd = 'zhang111';
            $dbname = 'wangzhan';

            $dsn = "mysql:host=$host;dbname=$dbname;port=3306";
            $pdo = new PDO ( $dsn, $user, $pwd );
            $pdo->query('set names utf8;');
            $pdo->setAttribute(PDO::ATTR_EMULATE_PREPARES, false);
            $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            self::$pdo = $pdo;
        }
        return self::$pdo;
    }

    public static function getStmt ( $sql )
    {
        $pdo = self::getPdo ();
        return $pdo -> prepare( $sql );
    }
}


$sql = "INSERT INTO testss (wef,wef1) VALUES(?,?)";
$stmt = Db::getStmt ( $sql );
$stmt = Db::getStmt ( $sql );


?>
  ';
        if ( self::$pdo =