讓我解釋一下我想要什么。我想在輸入時(shí)使用 db add 在列表中添加一個(gè)值，而無需更改頁面form，然后單擊submit。但是在這段代碼中，我必須再刷新一次才能添加，并且一次也添加了兩次。我怎樣才能做到這一點(diǎn)？<?php    $conn = mysqli_connect('127.0.0.1','MYID','MYPASS','MYDB');    $sql = "SELECT * FROM MYTABLE";    $rs = mysqli_query($conn, $sql);    $list = '';    while($row = mysqli_fetch_array($rs)) {            $list = $list."<li><a href=\"index.php?id={$row['id']}\">{$row['title']}</a></li>";    }    $article = array(        'title' => 'Welcome!',        'description' => 'Hello, Web!'    );    if (isset($_GET['id'])){        $filtered_id = mysqli_real_escape_string($conn, $_GET['id']);        $sql = "SELECT * FROM topic WHERE id={$filtered_id}";        $rs = mysqli_query($conn, $sql);        $row = mysqli_fetch_array($rs);        $article['title'] = $row['title'];        $article['description'] = $row['description'];    }    if ($_POST['title'] != null){        $sql_in = "INSERT INTO topic (title, description, created) VALUES ('{$_POST['title']}', '{$_POST['description']}', NOW())";        $rs_in = mysqli_query($conn, $sql_in);        if ($rs_in === false) {                $msg = mysqli_error($conn);        } else {                $msg = 'Success.';        }    } else {        $msg = 'Fill in';    }?>