评论系统PHP和MySQL

我在互联网上找到了不错的评论系统脚本，但我不知道如何在评论中添加作者。你能帮我吗？我试着去做，但失败了。下面是评论系统功能的一些代码。

<?php
    function get_comments($file_id) {
        include 'database.php';
        $result = mysqli_query($connect, "SELECT * FROM `comments` WHERE `file_id`='$file_id' AND `is_child`=FALSE ORDER BY `date` DESC");
        $row_cnt = mysqli_num_rows($result);
        echo '<h1>Comments ('.$row_cnt.')</h1>';
        echo '<div class="comment">';
            new_comment();
        echo '</div>';
        foreach($result as $item) {
            $date = new dateTime($item['date']);
            $date = date_format($date, 'M j, Y | H:i:s');
            $auth = $item['author'];
            $par_code = $item['com_code'];
            $chi_result = mysqli_query($connect, "SELECT * FROM `comments` WHERE `par_code`='$par_code' AND `is_child`=TRUE");
            $chi_cnt = mysqli_num_rows($chi_result);
            echo '<div class="comment" name="'.$item['com_code'].'">'
                    .'<span class="author">'.$auth.'</span><br />'
                    .$item['comment'].'<br />'
                    .'<span class="date">Posted: '.$date.'</span><br />';
                    if($chi_cnt == 0) {
                        echo '<span class="replies">No replies</span>'
                            .'<span class="replies">&emsp;Reply</span>';
                    } else {
                        echo '<span class="replies">[+] '.$chi_cnt.' replies</span>'
                            .'<span class="replies"&emsp;Reply</span>';
                            add_comment($item['author'], $item['com_code']);
                        echo '<div name="children" id="children">';
                        foreach($chi_result as $com) {
                            $chi_date = new dateTime($com['date']);
                            $chi_date = date_format($chi_date, 'M j, Y | H:i:s');
                            echo '<div class="child" name="'.$com['com_code'].'">'
                                    .'<span class="author">'.$com['author'].'</span><br />'
                                    .$com['comment'].'<br />'
                                    .'<span class="date">Posted: '.$chi_date.'</span><br />'
                                .'</div>';
                        }
                        echo '</div>';
                    }
                echo '</div>';
        }
        mysqli_close($connect);
    }
    function add_comment($reply, $code) {
        echo '<form action="reply.php" method="post" enctpye="" name="new_comment">'
                .'<input type="hidden" name="par_code" value="'.$code.'" />'
                .'<textarea class="text_cmt" name="text_cmt" placeholder="Reply to '.$reply.'"></textarea><br />'
                .'<input type="submit" value="Reply" />'
            .'</form>';
    }
    function new_comment() {
        echo '<form action="new.php" method="post" enctpye="" name="new_comment">'
                .'<textarea class="text_cmt" name="text_cmt" placeholder="Post a new comment"></textarea><br />'
                .'<input type="submit" value="Post" />'
            .'</form>';
    }
    function generateRandomString($length = 10) {
        $characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
        $characterLength = strlen($characters);
        $randomString = '';
        for($i = 0; $i < $length; $i++) {
            $randomString .= $characters[rand(0, $characterLength - 1)];
        }
        return $randomString;
    }
    function checkString($com_code) {
        include 'database.php';
        $rand = generateRandomString();
        $result = mysqli_query($connect, "SELECT * FROM `comments` WHERE `com_code`='$com_code'");
        $row_cnt = mysqli_num_rows($result);
        if($row_cnt != 0) {
            return $rand;
        } else {
            checkString($rand);
        }
    }
?>

这是一个新评论的功能

<?php
    require_once 'database.php';
    require_once 'functions.php';
    $reply = $_REQUEST['text_cmt'];
    $date = date('Y-m-d H:i:s');
    $rand = generateRandomString();
        #checkString($rand);
    mysqli_query($connect, "INSERT INTO `comments` (`file_id`, `comment`, `com_code`, `is_child`, `par_code`, `author`, `date`) VALUES ('1234', '$reply', '$rand', '', '', 'guest', '$date')");
    header("Location: http://orfi.uwm.edu.pl/~s119434/przepis1");
?>