在 PHP 中构建线程消息的嵌套列表时遇到问题

Question

我正在构建一个非常简单的线程消息系统，主要用于我站点的用户在我扩展站点功能时向我和彼此传达错误和问题。但是，我没有运气创建每个线程的正确嵌套列表。

我有两个表：Threads 和 Posts，我在此处对其进行了简化以进行演示。

Threads 表大致如此，按最近修改的线程排序：

+----+-----------------+---------------------+

| id | thName          | thModified          |

+----+-----------------+---------------------+

| 5  | Thread Number 5 | 2019-06-29 20:54:59 |

+----+-----------------+---------------------+

| 4  | Thread Number 4 | 2019-06-29 20:45:22 |

+----+-----------------+---------------------+

| 3  | Thread Number 3 | 2019-06-29 20:44:20 |

+----+-----------------+---------------------+

| 2  | Thread Number 2 | 2019-06-29 20:43:00 |

+----+-----------------+---------------------+

| 1  | Thread Number 1 | 2019-06-29 20:39:25 |

+----+-----------------+---------------------+

其中每个帖子都与另一个表上的一个线程相关，并且通过解析 parentID 列在此表中确定父/子关系。以“0”为父节点的帖子是根节点。

我的基本攻击计划是这样的：

1. 获取所有线程，按最近排序

2. 对于每个线程，通过匹配 thread_ids 获取所有帖子，按 parent_id 排序

3. 对于每个线程，以某种方式（递归？）遍历这个帖子列表并创建一个 PHP 有序列表，正确缩进显示父子之间的关系。

可悲的是，这是过去 3 天让我完全停滞不前的最后一步。

从该数组中，我想生成一个类似于以下内容的嵌套列表：

Thread Number 5 - First message of thread number 5
    Thread Number 5 - Second response to post 5
    Thread Number 5 - First response to post 5
        Thread Number 5 - First response to post 6

请注意，响应按发布日期排序（最近的优先），当然对于后续线程，我希望缩进再次回到零位置。

添加以澄清意图：在生产中，每个帖子都是一个链接，打开以显示消息的全文。响应将是相同的“线程名称”，并附加了用户和日期。因此，例如，胎面可能会显示“登录期间发现错误”，而我的回复（第一个孩子）将显示：“登录期间发现错误 - Chris Conlee 19/07/01 09:10”我意识到上面的示例在没有语境。

老实说，我没有任何运行良好的代码可以在这里发布。有一次，我有一个递归例程，它只遍历最左边的那条腿，然后跳过第二个响应到帖子 5。

在另一点上，我有一个例程，以重复和三次显示所有节点，并且缩进从未正常工作。

我深表歉意，因为它看起来应该是一个非常简单的练习，但我只是把自己弄成一个结，试图让我的头脑围绕它的递归性质，再加上多线程等。如果有人能给我一条生命线非常感谢。

Answer 1

好吧，我终于放慢了速度，逐个元素地遍历迭代并弄清楚了。提供与给定线程相关的一系列帖子，例如：[0] => Array&nbsp; &nbsp; &nbsp; &nbsp; (&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_id] => 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_id] => 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [parent_id] => 0&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [user_id] => 9&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_message] => First message of thread number 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_created] => 2019-06-29 20:54:59&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_title] => Thread Number 5&nbsp; &nbsp; &nbsp; &nbsp; )&nbsp; &nbsp; [1] => Array&nbsp; &nbsp; &nbsp; &nbsp; (&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_id] => 6&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_id] => 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [parent_id] => 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [user_id] => 9&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_message] => First response to post 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_created] => 2019-06-29 21:39:00&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_title] => Thread Number 5&nbsp; &nbsp; &nbsp; &nbsp; )&nbsp; &nbsp; [2] => Array&nbsp; &nbsp; &nbsp; &nbsp; (&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_id] => 7&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_id] => 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [parent_id] => 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [user_id] => 9&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_message] => Second response to post 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_created] => 2019-06-29 21:52:00&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_title] => Thread Number 5&nbsp; &nbsp; &nbsp; &nbsp; )&nbsp; &nbsp; [3] => Array&nbsp; &nbsp; &nbsp; &nbsp; (&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_id] => 8&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_id] => 5&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [parent_id] => 6&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [user_id] => 0&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_message] => First response to post 6&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [post_created] => 2019-06-29 21:55:00&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; [thread_title] => Thread Number 5&nbsp; &nbsp; &nbsp; &nbsp; )进入以下方法：public function buildForum($postsToThread, &$forum, $parent_id = 0) {&nbsp; &nbsp; foreach ($postsToThread as $post) {&nbsp; &nbsp; &nbsp; &nbsp; $time = strtotime($post['post_created']);&nbsp; &nbsp; &nbsp; &nbsp; $tmpCurrentAuthorName = $this->getPostAuthor($post['user_id']);&nbsp; &nbsp; &nbsp; &nbsp; $tmpCurrentThreadTitle = $post['thread_title'];&nbsp; &nbsp; &nbsp; &nbsp; $tmpCurrentPostDate = date("M d, Y g:i A", $time);&nbsp; &nbsp; &nbsp; &nbsp; if ($post['parent_id'] == $parent_id) {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; $forum .= "<ol><li><a href='/freetools/forumViewPost/" .$post['post_id'] . "'>" . $tmpCurrentThreadTitle .= " by " . $tmpCurrentAuthorName . "</a> on " . $tmpCurrentPostDate . "</li>";&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; $parent_id = $post['post_id'];&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; $this->buildForum($postsToThread, $forum, $parent_id);&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; $parent_id = $post['parent_id'];&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; $forum .= "</ol>";&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }}