PHP - PDO app error [duplicate] - php

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"Notice: Undefined variable", "Notice: Undefined index", "Warning: Undefined array key", and "Notice: Undefined offset" using PHP
(29 answers)
Closed 6 years ago.
I'm trying to extend my PDO knowledge and at the moment I'm working at php app. Actually is a simple CMS, and I got a problem on the admin page, when you try to update the existing pages I got an error about ID [$_POST].
The error looks like:
Notice: Undefined index: id in /Applications/MAMP/htdocs/cms/admin/edit.php on line 6 object(PDOStatement)#2 (1) { ["queryString"]=> string(138) " UPDATE pages SET label = :label, title = :title, slug = :slug, body = :body, updated = NOW(), WHERE id = :id " } Warning: Cannot modify header information - headers already sent by (output started at /Applications/MAMP/htdocs/cms/admin/edit.php:6) in /Applications/MAMP/htdocs/cms/admin/edit.php on line 28
EDIT.php
<?php
require '../app/start.php';
if (!empty($_POST)) {
$id = $_POST['id'];
$label = $_POST['label'];
$title = $_POST['title'];
$slug = $_POST['slug'];
$body = $_POST['body'];
$updatePage = $db->prepare('
UPDATE pages
SET label = :label, title = :title, slug = :slug, body = :body, updated = NOW(),
WHERE id = :id
');
$updatePage->execute([
'id' => $id,
'label' => $label,
'title' => $title,
'slug' => $slug,
'body' => $body,
]);
var_dump($updatePage);
header('Location: ' . BASE_URL . '/admin/list.php');
exit();
}
if(!isset($_GET['id'])){
header('Location:' . BASE_URL . '/admin/list.php');
exit();
}
$page = $db->prepare('
SELECT *
FROM pages
WHERE id = :id
');
$page->execute(['id' => $_GET['id']]);
$page = $page->fetch(PDO::FETCH_ASSOC);
require VIEW_ROOT . '/admin/edit.php';
START.php
<?php
require ('functions.php');
ini_set('display_errors', 1);
define('APP_ROOT', __DIR__);
define('VIEW_ROOT', APP_ROOT . '/views');
define('BASE_URL', 'http://localhost/cms');
$db = new PDO('mysql:host=localhost;dbname=cms', 'root', 'root');
?>
EDIT.PHP (form page)
<?php require VIEW_ROOT . '/templates/header.php'; ?>
<h2>Add page</h2>
<form action="<?php echo BASE_URL; ?>/admin/edit.php" method="POST" autocomplete="off">
<label for="title">
Title
<input type="text" name="title" id="title" value="<?php echo e($page['title']); ?>">
</label>
<label for="label">
Label
<input type="text" name="label" id="label" value="<?php echo e($page['label']); ?>">
</label>
<label for="slug">
Slug
<input type="text" name="slug" id="slug" value="<?php echo e($page['slug']); ?>">
</label>
<label for="body">
Content
<textarea name="body" id="body" cols="30" rows="10"><?php echo e($page['body']); ?></textarea>
</label>
<input type="hidden" value="<?php echo e($page['id']);?>">
<input type="submit" value="Edit article">
</form>

Answer 1

check following code:
<input type="hidden" value="<?php echo e($page['id']);?>">
as you see this code does not have name , according to your samples it should have name="id"