由于本地 PHP 版本过底,没办法进行完整的测试

$host = 'localhost';

$user = 'root';

$password = '';

$dbname = 'cmstop';

$mysqli = new mysqli($host, $user, $password, $dbname) or exit('无法连接到mysql:'.$mysqli->connect_error);

 $sql  = "SELECT CURRENT_USER(); SELECT * FROM `db_setting` LIMIT 5;";

if ($mysqli->multi_query($sql)){//多条查询

    do{

        if($result = $mysqli->store_result()){//如果还有还结果集,取当前的一个结果集返回

            while($row = $result->fetch_row()){//取一条记录

                echo $row[0];

            }

            $result->free();//当此结果集中无记录时,释放

        }

        if($mysqli->more_results()){//如果还有一个结果集,则输出分隔线

            echo "<hr />";

        }

    }while($mysqli->next_result());

}

//预处理

$sql = "SELECT `app`,`var` FROM `db_setting` WHERE `app`=? LIMIT 5";

$app = 'article';

$stmt = $mysqli->stmt_init();

if($stmt->prepare($sql)) {

    $stmt->bind_param("s", $app);

    $stmt->execute();//执行查询

    

    $stmt->bind_result($field1, $field2); //生成两个字段的结果集

    while ($stmt->fetch()) {

        echo '<br/>', $field1,' => ', $field2;

    }

    echo'<hr/>';

    

    $app = 'guestbook';

    $stmt->execute();//执行查询

    $result = $stmt->get_result(); //生成两个字段的结果集

    while ($row = $result->fetch_array(MYSQLI_NUM)){

        echo $row[0],' => ',$row[1];

    }

    

    $stmt->close();

}

$mysqli->close();