Ausführliche Erklärung, wie die Funktion zum Antworten und Löschen von Kommentaren in PHP implementiert wird

<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
<h1>朋友圈</h1>
<p>内容:</p>
<p>今天很嗨</p>
<p><img src="../picture/timg.jpg" width="300" height="200"></p><br>
<form action="mainchuli.php" method="post">
    <input type="text" hidden="hidden" value="zhangsan" name="zhangsan"> <!--因为没有权限，这里给了一个默认值-->
    <textarea name="content"></textarea><input type="submit" value="评论"><!--评论显示的地方--><!--单击评论提交内容进处理页面-->
</form>
 
<!--?php
  require"DBDA.class.php"; //调用封装类注意修改数据库名
  $db = new DBDA();
  $sql ="select * from Pinglun";
  $arr = $db--->query($sql,1);
  foreach($arr as $v)
  {
    echo"
       <p style="color:blue">{$v[1]} {$v[3]}</p>
       <p style="color:blue">{$v[2]}</p>
       <form action="delchuli.php?id={$v[0]}" method="post"> //删除按钮
        <input type="submit" value="删除">
       </form>
       <form action="huifuchuli.php?id={$v[0]}" method="post"> //回复按钮
        <textarea name="Comment"></textarea><input type="submit" value="回复">
       </form>
       ";
       
      $dc = new DBDA(); 
      $sql1 ="select * from huifu where jieshouid ={$v[0]}"; //查询回复表中的id和传过去的id是不是一样的
          $arr1 = $dc->query($sql1,1);
      foreach($arr1 as $k)
      {
        echo "<p>{$k[2]} {$k[3]}</p>
           <p>{$k[4]}</p>
           ";
      }
         
  }   
?>

<?php
$zhangsan = $_POST["zhangsan"];
$content = $_POST["content"];
$time = date("Y-m-d H:i:s");
 
require "DBDA.class.php";
$db = new DBDA();
$sql = "insert into Pinglun values(&#39;&#39;,&#39;{$zhangsan}&#39;,&#39;{$content}&#39;,&#39;{$time}&#39;)";
$db->query($sql);
header("location:main.php");

<!--?php
$id = $_GET["id"]; //将点击回复的评论id传过来
$Comment = $_POST["Comment"]; //回复文本域中的内容
$me = "me"; //这里是给定义了一个人
$Times = date("Y-m-d H:i:s");
 
require "DBDA.class.php";
$db = new DBDA();
$sql = "insert into huifu values(&#39;&#39;,&#39;{$id}&#39;, &#39;{$me}&#39;,&#39;{$Times}&#39;,&#39;{$Comment}&#39;)";
$db--->query($sql);
header("location:main.php");

<?php
$id = $_GET["id"];
require "DBDA.class.php";
$db = new DBDA();
$sql = "delete from Pinglun where id=&#39;{$id}&#39;";
if($db->query($sql))
{
 
  header("location:main.php");
}
else
{
  echo "删除失败！";
}