To remove all custom post, you can use the fallowing PHP script in your uninstall.php file or function/method defined in your plugin. For example, let’s pretend we are uninstalling a book custom post type plugin:
$books = get_posts(['post_type' => 'book', 'numberposts' => -1]);
foreach ($books as $book) {
wp_delete_post($book->ID, true); // 'true' stands for force delete (delete if privet draft and so on ...)
}If you plan on removing also a custom post and meta values stored in database, you might want to use an SQL query instead. Notice. In the query below, I use SELECT instead of DELETE clause. Never delete anything from a database unless you investigated the output first. So if you’re happy with the data you get back, you might swap SELECT with DELETE.
global $wpdb;
$wpdb->query("SELECT * FROM wp_posts WHERE post_type = 'book'");
$wpdb->query("SELECT * FROM wp_postmeta WHERE post_id NOT IN (SELECT id FROM wp_posts)");
$wpdb->query("SELECT * FROM wp_term_relationship WHERE object_id NOT IN (SELECT id FROM wp_posts)");You can run the above SQL QUERY in plugin unistall.php file or in one of your function/methods registered with WP build in function register_uninstall_hook( string $file, callable $callback )
You might also go ahead and register uninstall static method, for example:
<?php
/**
* Shortcode class. PHP version 5.6+
*
* @category Plugin\MyPlugin
* @package MyPlugin
* @author Wiktor Liszkiewicz <w.liszkiewicz@gmail.com>
* @license all rights reserved
* @link none
*/
namespace Plugin\MyPlugin;
use Plugin\MyPlugin\CustomPluginOnActivate;
use Plugin\MyPlugin\CustomPluginOnDeactivate;
use Plugin\MyPlugin\CustomPluginOnUninstall;
use Plugin\MyPlugin\Admin\AdminSettingPage;
/**
* This class provide a set of shortcodes for woocommerce products,
* categories and tags related to post_type=product
*
* @category Plugin\MyPlugin
* @package MyPlugin
* @author Wiktor Liszkiewicz <w.liszkiewicz@gmail.com>
* @license all rights reserved
* @link tag in class commentphpcs
*/
class CustomPlugin
{
public static $pluginName = PLUGIN_NAME;
// private $postName = "book";
/*
* @var Plugin\MyPlugin\Admin\AdminSettingPage $_adminSettingPage
*/
private $_adminSettingPage;
/**
* Undocumented function
*
* @return void
*/
public function __construct()
{
CustomPluginOnActivate::registerActivationHook();
CustomPluginOnDeactivate::registerDeactivationHook();
CustomPluginOnUninstall::registerUninstallHook();
/* @var Plugin\MyPlugin\Admin\AdminSettingPage $this->_adminSettingPage */
$this->_adminSettingPage = new AdminSettingPage();
}
/**
* This function is responsible for registring js and css scripts
*
* @see $this->enqueueAdmin() and $this->enqueueFront() methods
*
* @return void
*/
public function register()
{
add_action('admin_enqueue_scripts', [$this, 'enqueueAdmin']);
add_action('wp_enqueue_scripts', [$this, 'enqueueFront']);
// add_action('init', [$this, 'registerPostType']);
$this->_adminSettingPage->register();
}
/**
* Enque css and js for admin area.
*
* @return void
*/
public function enqueueAdmin()
{
wp_enqueue_style('adminpluginstyles', plugins_url('/assets/admin/admin.css', PLUGIN_MAIN_FILE));
wp_enqueue_style('adminpluginscripts', plugins_url('/assets/admin/admin.js', PLUGIN_MAIN_FILE));
}
/**
* Enque css and js for fornt area.
*
* @return void
*/
public function enqueueFront()
{
wp_enqueue_style('frontpluginstyles', plugins_url('/assets/styles.css', PLUGIN_MAIN_FILE));
wp_enqueue_style('frontpluginscripts', plugins_url('/assets/script.js', PLUGIN_MAIN_FILE));
}
}
Then here you would create another file:
<?php
/**
* Shortcode class. PHP version 5.6+
*
* @category Plugin\MyPlugin\Front
* @package MyPlugin
* @author Wiktor Liszkiewicz <w.liszkiewicz@gmail.com>
* @license all rights reserved
* @link none
*/
namespace Plugin\MyPlugin;
if (! defined('ABSPATH')) {
die('No direct access allowed');
}
/**
* CustomPluginOnUninstall class is responsible to remove all data and
* files from WP system when user decide to delete the extension.
*
* Beofre using this functionality make sure to create database backup!
*
* @category Plugin\MyPlugin
* @package MyPlugin
* @author Wiktor Liszkiewicz <w.liszkiewicz@gmail.com>
* @license all rights reserved
* @link none
*/
class CustomPluginOnUninstall
{
/**
* Static method - Select and remove all data from
* custom post registeded by this plugin.
*
* @return void
*/
public static function uninstall()
{
global $wpdb;
/**
* TEST OUTPUT BEFORE CHANGING TO "DELETE"
*
* This query removes all asosiations in post_meat to
* non exsisting posts in wp_posts table.
*/
$wpdb->query("SELECT * FROM wp_posts WHERE post_type = 'book'");
$wpdb->query("SELECT * FROM wp_postmeta WHERE post_id NOT IN (SELECT id FROM wp_posts)");
$wpdb->query("SELECT * FROM wp_term_relationship WHERE object_id NOT IN (SELECT id FROM wp_posts)");
/* Uncoment only if SELECT output was tested (TEST FIRST!) */
// $wpdb->query("DELETE FROM wp_posts WHERE post_type = 'book'");
// $wpdb->query("SELECT FROM wp_postmeta WHERE post_id NOT IN (SELECT id FROM wp_posts)");
// $wpdb->query("SELECT FROM wp_term_relationship WHERE object_id NOT IN (SELECT id FROM wp_posts)");
/* ALTERNATIVLY USE */
// $books = get_posts(['post_type' => 'book', 'numberposts' => -1]);
// foreach ($books as $book) {
// wp_delete_post($book->ID, true); // 'true' stands for force delete (delete if privet draft and so on ...)
// // add delete_post_meta() // you need to know the post meta keys here so you might need to query them first with SQL
// }
}
/**
* Static function which will call the unistall method of this class
* Note the use of __CLASS__ instead of this as this is a static method.
*
* @see called in CustomPlugin class in __construct method
*
* @return void
*/
public static function registerUninstallHook()
{
register_uninstall_hook(PLUGIN_MAIN_FILE, [ __CLASS__, 'uninstall' ]);
}
}
https://hotexamples.com/examples/-/-/delete_post_meta/php-delete_post_meta-function-examples.html
https://www.youtube.com/watch?v=x3ID1cyafvE