MYSQL删除特定的行按钮PHP

Question

I am building a very basic forum with the ability to comment on posts. As you can see, this code shows the commments and when the comment author is equal to the logged in user, it should show a delete button to delete the comment. The problem is now that when I click the delete button, it deletes all the comments on the post and not only the comment with the delete button next to it.

My 'comments' table has the columns id, discid, comment_username, comment and comment_time in which the discid column from 'comments' refers to the id column in the table 'dicussions'

    <?php

    $id = mysql_real_escape_string($_GET['id']);
    $query = 'SELECT * FROM discussions WHERE `id` = '.$id.' LIMIT 1';
    $result = mysql_query($query);
    $row = mysql_fetch_array($result);

    ?>
            <h2><? echo $row['category'] . $row['topic']; ?></h2>
            <div>Posted on <? echo $row['date_time']; ?> by <? echo $row['username'] ?></div>
            <div><? echo $row['discussion']; ?></div>

     <?

$result_comments = mysql_query("SELECT * FROM comments WHERE discid = $id ORDER BY comment_time ASC");

        while ($record = mysql_fetch_array($result_comments))

        {

        ?>
                <form action="" method="POST" >
                  <? echo $record['comment_username']. $record['comment_time'] ?>   

                  <!-- if comment from logged in user, show delete option -->
                  <? 
                  if ($record['comment_username'] == $log_username) 
                    { 
                      echo '<span><button title="Delete comment" value="' . $record['id'] .'" name="deletecommentbutton" type="submit">X</button></span>';
                    } 
                    if(isset($_POST['deletecommentbutton']))
                    { 
                      $commentid = $record['id'];
                      $result_delete = mysql_query("DELETE from comments WHERE id='$commentid'");
                      header("Location: url/discussion_view.php?id=".$_GET['id']."");
                    }
                  ?>

                <div><? echo $record['comment'] ?></div></form>

          <?php } ?>

Answer 1

First of all you should not use mysql_* functions anymore. It's deprecated.

Instead you can use PDO .

And about your problem, statement if(isset($_POST['deletecommentbutton'])) is true for every comment on given post because you are not checking ID of selected comment. You should move deletion code outside of loop and execute it only for selected ID.