search
HomeBackend DevelopmentPHP TutorialDetailed explanation of steps to implement unlimited comment nesting in PHP

This time I will bring you a detailed explanation of the steps to implement unlimited comment nesting in PHP. What are the precautions for implementing unlimited comment nesting in PHP? The following is a practical case, let's take a look.

In the process of designing BB, I have been thinking about whether it is possible to achieve infinite classification structure display and parent-child structure search without recursion, because if the algorithm here is not optimized, the consequences may be fatal! Just imagine, if an article has 300 comments, according to the normal recursive algorithm, the database must be queried at least 301 times, and this is without any nesting. If there are one or two levels of nesting or the number of comments exceeds 1,000 , then the database doesn’t crash directly?

In fact, PHP's powerful array processing capabilities can already help us solve this problem quickly and conveniently. The following figure shows an infinite-level classified

database structure:

IDparentID newsID commts

108 comments with article ID 8
21 8 replies to comments with ID 1
328 Reply to the comment with ID 2

To display the comment with article number 8 in the front desk in a nested manner, in fact, we only need to query the database once, that is, "SELECT * FROM TABLE WHERE newsID=8" , and leave the later recursive work to the powerful

PHP array. The problem that may be involved here is the reorganization of the structural relationship of the array, that is, putting all the comments that stay in the first-level category under their own parentID to form the children item. Paste the code of this piece of code in the BBComment class below. I hope to share my ideas with you, and hope that everyone can come up with better and more efficient algorithms.

Method One

/** 
 * 按ID条件从评论数组中递归查找 
 * 
 */ 
function getCommentsFromAryById($commtAry, $id) 
{ 
 if ( !is_array($commtAry) ) return FALSE; 
 foreach($commtAry as $key=>$value) { 
  if ( $value['id'] == $id ) return $value; 
  if ( isset($value['children']) && is_array($children) ) $this->getCommentsFormAryById($value['children'], $id); 
 } 
} 
/** 
 * 追加 子评论 到 主评论 中,并形成children子项 
 * 
 * @param array $commtAry 原评论数据引用 
 * @param int $parentId 主评论ID 
 * @param array $childrenAry 子评论的值 
 */ 
function addChildenToCommentsAry($commtAry, $parentId, $childrenAry) 
{ 
 if ( !is_array($commtAry) ) return FALSE; 
 foreach($commtAry as $key=>$value) { 
  if ( $value['id'] == $parentId ) { 
   $commtAry[$key]['children'][] = $childrenAry; 
   return TRUE; 
  } 
  if ( isset($value['children']) ) $this->addChildenToCommentsAry($commtAry[$key]['children'], $parentId, $childrenAry); 
 } 
} 
 $result = $this->BBDM->select($table, $column, $condition, 0, 1000); 
 /* 开始进行嵌套评论结构重组 */ 
 array_shift($result); 
 $count = count($result); 
 $i  = 0; 
 while( $i<$count ) { 
  if ( &#39;0&#39; != $result[$i][&#39;parentId&#39;] ) { 
   $this->addChildenToCommentsAry($result, $result[$i][&#39;parentId&#39;], $result[$i]); 
   unset($result[$i]); 
  } 
  $i++; 
 } 
 $result = array_values($result); 
 /* 重组结束 */

Implementation Method Two

The core code is extracted from WordPress

<?php
$comments = array (
  array (
    &#39;id&#39; => &#39;3&#39;,
    &#39;parent&#39; => &#39;0&#39;
  ),
  array (
    &#39;id&#39; => &#39;9&#39;,
    &#39;parent&#39; => &#39;0&#39;
  ),
  array (
    &#39;id&#39; => &#39;1&#39;,
    &#39;parent&#39; => &#39;3&#39;
  ),
  array (
    &#39;id&#39; => &#39;2&#39;,
    &#39;parent&#39; => &#39;3&#39;
  ),
  array (
    &#39;id&#39; => &#39;5&#39;,
    &#39;parent&#39; => &#39;1&#39;
  ),
  array (
    &#39;id&#39; => &#39;7&#39;,
    &#39;parent&#39; => &#39;1&#39;
  )
);
function html5_comment($comment) {
  echo &#39;<li>&#39;;
  echo &#39;id:&#39;, $comment[&#39;id&#39;], &#39; parent:&#39;, $comment[&#39;parent&#39;];
}
function start_el(& $output, $comment) {
  ob_start();
  html5_comment($comment);
  $output .= ob_get_clean();
}
function end_el(& $output) {
  $output .= "</li><!-- #comment-## -->\n";
}
function start_lvl(& $output) {
  $output .= &#39;<ol class="children">&#39; . "\n";
}
function end_lvl(& $output) {
  $output .= "</ol><!-- .children -->\n";
}
function display_element($e, & $children_elements, $max_depth, $depth, & $output) {
  $id = $e[&#39;id&#39;];
  start_el($output, $e); //当前评论的开始代码
  if ($max_depth > $depth +1 && isset ($children_elements[$id])) { //如果没超过最大层,并且存在子元素数组
    foreach ($children_elements[$id] as $child) {
      if (!isset ($newlevel)) { //第一次循环没设置变量$newlevel,所以把$newlevel设为true,并且开始子元素的开始代码;第二次及之后的循环,已经设置了$newlevel,就不会再添加子元素的开始代码。因为同一批循环时兄弟元素,所以只需要一个子元素开始代码,循环内容为并列关系。
        $newlevel = true;
        start_lvl($output);
      }
      display_element_template($child, $children_elements, $max_depth, $depth +1, $output); //$child作为参数,继续去寻找下级元素
    }
    unset ($children_elements[$id]); //用完释放变量,以后就不会重复判断该值了,递归后继续判断剩下的子元素
  }
  if (isset ($newlevel) && $newlevel) { //如果前面找到了子元素,这里就要执行子元素的结束代码
    end_lvl($output);
  }
  end_el($output); //当前评论的结束代码
}
function display_element_template($e, & $children_elements, $max_depth, $depth, & $output) {
  $id = $e[&#39;id&#39;];
  display_element($e, $children_elements, $max_depth, $depth, $output);
  if ($max_depth <= $depth +1 && isset ($children_elements[$id])) { //如果超出最大层级,并且子元素存在的话,以$child为参数继续往下找
    foreach ($children_elements[$id] as $child) {
      display_element_template($child, $children_elements, $max_depth, $depth, $output);
    }
    unset ($children_elements[$id]); //用完释放变量
  }
}
function comments_list($comments) {
  $top_level_elements = array ();
  $children_elements = array ();
  foreach ($comments as $e) {
    if (0 == $e[&#39;parent&#39;]) {
      $top_level_elements[] = $e;
    } else {
      $children_elements[$e[&#39;parent&#39;]][] = $e;
    }
  }
  $output = &#39;&#39;;
  foreach ($top_level_elements as $e) {
    display_element_template($e, $children_elements, 2, 0, $output);
  }
  //var_dump($children_elements);//由于每次用完$children_elements后都会释放变量,所以到最后$children_elements为空数组
  return $output;
}
echo &#39;<ol class="comment-list">&#39;, comments_list($comments), &#39;</ol>&#39;;

I believe you have mastered it after reading the case in this article Method, for more exciting information, please pay attention to other related articles on the php Chinese website!

Recommended reading:

php curl with csrf-token verification simulation submission example detailed explanation

php implements database addition and deletion query Detailed explanation of the steps

The above is the detailed content of Detailed explanation of steps to implement unlimited comment nesting in PHP. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
How do you modify data stored in a PHP session?How do you modify data stored in a PHP session?Apr 27, 2025 am 12:23 AM

TomodifydatainaPHPsession,startthesessionwithsession_start(),thenuse$_SESSIONtoset,modify,orremovevariables.1)Startthesession.2)Setormodifysessionvariablesusing$_SESSION.3)Removevariableswithunset().4)Clearallvariableswithsession_unset().5)Destroythe

Give an example of storing an array in a PHP session.Give an example of storing an array in a PHP session.Apr 27, 2025 am 12:20 AM

Arrays can be stored in PHP sessions. 1. Start the session and use session_start(). 2. Create an array and store it in $_SESSION. 3. Retrieve the array through $_SESSION. 4. Optimize session data to improve performance.

How does garbage collection work for PHP sessions?How does garbage collection work for PHP sessions?Apr 27, 2025 am 12:19 AM

PHP session garbage collection is triggered through a probability mechanism to clean up expired session data. 1) Set the trigger probability and session life cycle in the configuration file; 2) You can use cron tasks to optimize high-load applications; 3) You need to balance the garbage collection frequency and performance to avoid data loss.

How can you trace session activity in PHP?How can you trace session activity in PHP?Apr 27, 2025 am 12:10 AM

Tracking user session activities in PHP is implemented through session management. 1) Use session_start() to start the session. 2) Store and access data through the $_SESSION array. 3) Call session_destroy() to end the session. Session tracking is used for user behavior analysis, security monitoring, and performance optimization.

How can you use a database to store PHP session data?How can you use a database to store PHP session data?Apr 27, 2025 am 12:02 AM

Using databases to store PHP session data can improve performance and scalability. 1) Configure MySQL to store session data: Set up the session processor in php.ini or PHP code. 2) Implement custom session processor: define open, close, read, write and other functions to interact with the database. 3) Optimization and best practices: Use indexing, caching, data compression and distributed storage to improve performance.

Explain the concept of a PHP session in simple terms.Explain the concept of a PHP session in simple terms.Apr 26, 2025 am 12:09 AM

PHPsessionstrackuserdataacrossmultiplepagerequestsusingauniqueIDstoredinacookie.Here'showtomanagethemeffectively:1)Startasessionwithsession_start()andstoredatain$_SESSION.2)RegeneratethesessionIDafterloginwithsession_regenerate_id(true)topreventsessi

How do you loop through all the values stored in a PHP session?How do you loop through all the values stored in a PHP session?Apr 26, 2025 am 12:06 AM

In PHP, iterating through session data can be achieved through the following steps: 1. Start the session using session_start(). 2. Iterate through foreach loop through all key-value pairs in the $_SESSION array. 3. When processing complex data structures, use is_array() or is_object() functions and use print_r() to output detailed information. 4. When optimizing traversal, paging can be used to avoid processing large amounts of data at one time. This will help you manage and use PHP session data more efficiently in your actual project.

Explain how to use sessions for user authentication.Explain how to use sessions for user authentication.Apr 26, 2025 am 12:04 AM

The session realizes user authentication through the server-side state management mechanism. 1) Session creation and generation of unique IDs, 2) IDs are passed through cookies, 3) Server stores and accesses session data through IDs, 4) User authentication and status management are realized, improving application security and user experience.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

PhpStorm Mac version

PhpStorm Mac version

The latest (2018.2.1) professional PHP integrated development tool

mPDF

mPDF

mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

MinGW - Minimalist GNU for Windows

MinGW - Minimalist GNU for Windows

This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

EditPlus Chinese cracked version

EditPlus Chinese cracked version

Small size, syntax highlighting, does not support code prompt function