Question

我正在使用SQL语句学习PHP，但在尝试创建删除按钮时遇到了问题。

问题是当我按下“删除”按钮时没有发生任何事情。查询运行正常，它从循环中获取正确的用户ID。

<?php
        require_once 'db_connect.php';

        $select = "SELECT * FROM Users";
        $result = mysqli_query($dbc, $select) or die('could not query database');


        while ($row = mysqli_fetch_assoc($result)) {

            echo '
            <tr>
                <td>' . $row['userid'] . '</td>
                <td>' . $row['fnamn'] . ' ' . $row['enamn'] . '</td>
                <td>' . $row['username'] . '</td>
                <td>' . $row['email'] . '</td>
                    <td>' . '<form action="" method="post">
                            <input type="button" name="delete" value="Radera" />
                        </form>' . '</td>

            </tr>';

            if(isset($_POST['delete'])) {

                $userid = $row['userid'];

                $delete = "DELETE FROM Users WHERE userid = '$userid' ";
                $result = mysqli_query($dbc, $delete) or die('could not query database');
            }
        }

        mysqli_close($dbc);
        ?>

Answer 1

你需要：

将您的if (isset($_POST['delete']))声明放在外面在while循环之前。
有一些方法可以知道你删除哪一行（也许是一个隐藏的输入）。

这样的事情：

<?php
require_once 'db_connect.php';

if(isset($_POST['delete']) && isset($_POST['user_id'])) {
    $userid = $_POST['user_id'];

    $delete = "DELETE FROM Users WHERE userid = '$userid' ";
    $result = mysqli_query($dbc, $delete) or die('could not query database');
}

$select = "SELECT * FROM Users";
$result = mysqli_query($dbc, $select) or die('could not query database');

while ($row = mysqli_fetch_assoc($result)) {
    echo '
    <tr>
        <td>' . $row['userid'] . '</td>
        <td>' . $row['fnamn'] . ' ' . $row['enamn'] . '</td>
        <td>' . $row['username'] . '</td>
        <td>' . $row['email'] . '</td>
        <td>' . '<form action="" method="post">
            <input type="hidden" name="user_id" id="user_id" value="'.$row['userid'].'" />
            <input type="submit" name="delete" id="delete" value="Radera" />
        </form>' . '</td>
    </tr>';
}

mysqli_close($dbc);
?>

我建议您不要像上面那样直接将$_POST['user_id']插入您的查询中;你会想要阅读准备好的陈述

Answer 2

替换类型。

而不是：

<input type="button" name="delete" value="Radera" />

尝试：

<input type="submit" name="delete" value="Radera" />

删除按钮不起作用

2 个答案: