php – 选择多行mysqli

我想将下面的MySQL查询更改为MySQLi(预处理语句),但我不知道如何操作,因为它有多行要选择.任何人都可以指出正确的方式.

$check_added_files = MysqL_query("select * from `vpb_uploads` where `username` = '".MysqL_real_escape_string($username)."' and `firstname` = '' and `image_one` != '' and `image_two` != '' and `image_three` != '' and `image_four` != '' and `image_five` != ''");
        if(MysqL_num_rows($check_added_files) == 1)
        {
            echo 'up_to_five_already';
        }

解决方法:

正确的方法是将其更改为PDO

$sql = "select * from vpb_uploads where username=? and firstname=''
        and image_one != '' and image_two != '' and image_three != '' 
        and image_four != '' and image_five != ''";
$stm = $pdo->prepare($sql);
$stm->execute(array($username));
$files = $stm->fetchAll();