表单输入中的数组 - Select 语句 MySQLi 参数化

Array from Form Input - Select Statement MySQLi Parameterisation

提问人:CGarden 提问时间:11/11/2019 更新时间:11/11/2019 访问量:56

问:

将表单输入中输入的短语转换为数组,以使用 MySQLi 传递到 MySQL select 语句 where 子句中。我拥有的 php 代码实现了这一点,但我无法练习如何参数化查询以防止 sql 注入攻击。我在这个网站上看了一些问题,但我正在努力将其与我的代码联系起来。

if(!empty($_POST['Message']))
{
      $searchStr = get_post($con,'Message');
      $aKeyword = explode(" ", $searchStr);

      $query ="SELECT m.ID, m.MessageText FROM MessageMain m LEFT OUTER JOIN Likes l on m.ID = l.PostID WHERE MessageText LIKE '%" . $aKeyword[0] . "%'";

     for($i = 1; $i < count($aKeyword); $i++) {
        if(!empty($aKeyword[$i])) {
            $query .= " OR MessageText like '%" . $aKeyword[$i] . "%'";
        }
      }

      $query .= " GROUP BY m.ID, m.MessageText ORDER BY count(m.id) desc";

       $result = $con->query($query);
       $rowcount=mysqli_num_rows($result);
php mysqli SQL注入

评论


答:

2赞 Dharman 11/11/2019 #1

如果你想根据要匹配的关键词数量动态地构建子句,你可以这样做:WHERE

if (!empty($_POST['Message'])) {
    $searchStr = get_post($con, 'Message');
    $aKeyword = explode(" ", $searchStr);

    $whereClauseArr = [];
    foreach ($aKeyword as $keyword) {
        if ($keyword) {
            $whereClauseArr[] = "MessageText LIKE ?";
            $whereValues[] = '%'.$keyword.'%';
        }
    }

    $stmt = $con->prepare(
        'SELECT m.ID, m.MessageText 
        FROM MessageMain m 
        LEFT OUTER JOIN Likes l on m.ID = l.PostID 
        WHERE '.implode(' OR ', $whereClauseArr).'
        GROUP BY m.ID, m.MessageText ORDER BY count(m.id) desc'
    );

    $stmt->bind_param(str_repeat('s', count($whereValues)), ...$whereValues);
    $stmt->execute();
    $result = $stmt->get_result();
}

尽管在您的情况下,使用正则表达式检查同一列是否符合多个值可能更好。这将使您的查询更简单,也可能更快,具体取决于您拥有的关键字数量。

if (!empty($_POST['Message'])) {
    $searchStr = get_post($con, 'Message');
    $aKeyword = explode(" ", $searchStr);

    $aKeyword = array_filter($aKeyword); // Remove empty values

    $stmt = $con->prepare(
        'SELECT m.ID, m.MessageText 
        FROM MessageMain m 
        LEFT OUTER JOIN Likes l on m.ID = l.PostID 
        WHERE MessageText REGEXP ?
        GROUP BY m.ID, m.MessageText ORDER BY count(m.id) desc'
    );

    $regexString = implode('|', $aKeyword);
    $stmt->bind_param('s', $regexString);
    $stmt->execute();
    $result = $stmt->get_result();
}

评论

1赞 CGarden 11/12/2019
谢谢你的上述内容。您的代码无需修改即可工作:)我学到了一些非常酷和有用的东西。再次感谢。我用了REGEXP的答案,只是想说!