Step 1: Create the Plugin Folder and File

1. Create a New Plugin Folder and File (if not already done)
   • Create a new folder in the wp-content/plugins directory, e.g., bulk-delete-categories.
   • Inside this folder, create a file named bulk-delete-categories.php.

Step 2: Add the Code:

<?php
/*
Plugin Name: Bulk Delete Categories with Feedback and Move Posts
Description: A plugin to bulk delete all categories with user feedback and move posts to “Uncategorized”.
Version: 1.2
Author: Your Name
*/

function move_posts_to_uncategorized() {
// Get the ID of the “Uncategorized” category
$uncategorized_id = get_cat_ID(‘Uncategorized’);

// Get all posts in the categories being deleted
$categories = get_categories(array(
‘hide_empty’ => false
));

foreach ($categories as $category) {
if ($category->term_id != $uncategorized_id) {
$posts = get_posts(array(
‘category’ => $category->term_id,
‘numberposts’ => -1
));

foreach ($posts as $post) {
wp_set_post_categories($post->ID, array($uncategorized_id), true);
}
}
}
}

function delete_all_categories_with_feedback() {
// Move posts to “Uncategorized” category
move_posts_to_uncategorized();

// Get all categories and delete them
$categories = get_categories(array(
‘hide_empty’ => false
));

foreach ($categories as $category) {
if ($category->term_id != get_cat_ID(‘Uncategorized’)) {
wp_delete_term($category->term_id, ‘category’);
}
}
}

function bulk_delete_categories_admin_notice($message, $type = ‘success’) {
?>
<div class=”notice notice-<?php echo esc_attr($type); ?> is-dismissible”>
<p><?php echo esc_html($message); ?></p>
</div>
<?php
}

// Add an admin menu item to trigger the deletion
function bulk_delete_categories_menu() {
add_submenu_page(
‘tools.php’, // Parent slug
‘Bulk Delete Categories’, // Page title
‘Bulk Delete Categories’, // Menu title
‘manage_options’, // Capability
‘bulk-delete-categories’, // Menu slug
‘bulk_delete_categories_page’ // Function to display the page content
);
}

function bulk_delete_categories_page() {
if (isset($_POST[‘bulk_delete_categories’])) {
check_admin_referer(‘bulk_delete_categories_nonce’);

// Perform the deletion
delete_all_categories_with_feedback();

// Add an admin notice
bulk_delete_categories_admin_notice(‘All categories have been successfully deleted and posts moved to “Uncategorized”.’);
?>
<div class=”wrap”>
<h1>Bulk Delete Categories</h1>
<p>The categories have been deleted. Please check your categories and posts.</p>
</div>
<?php
} else {
?>
<div class=”wrap”>
<h1>Bulk Delete Categories</h1>
<form method=”post”>
<?php wp_nonce_field(‘bulk_delete_categories_nonce’); ?>
<p>Click the button below to delete all categories and move posts to “Uncategorized”. This process may take some time if you have a lot of categories and posts.</p>
<p>
<input type=”hidden” name=”bulk_delete_categories” value=”true”>
<button type=”submit” class=”button button-primary”>Run</button>
</p>
</form>
</div>
<?php
}
}

add_action(‘admin_menu’, ‘bulk_delete_categories_menu’);