add_meta_box( string $id, string $title, callable $callback, string|array|WP_Screen $screen = null, string $context = 'advanced', string $priority = 'default', array $callback_args = null )
<?php
/**
* Register a meta box using a class.
*/
class WPDocs_Custom_Meta_Box {
/**
* Constructor.
*/
public function __construct() {
if ( is_admin() ) {
add_action( 'load-post.php', array( $this, 'init_metabox' ) );
add_action( 'load-post-new.php', array( $this, 'init_metabox' ) );
}
}
/**
* Meta box initialization.
*/
public function init_metabox() {
add_action( 'add_meta_boxes', array( $this, 'add_metabox' ) );
add_action( 'save_post', array( $this, 'save_metabox' ), 10, 2 );
}
/**
* Adds the meta box.
*/
public function add_metabox() {
add_meta_box(
'my-meta-box',
__( 'My Meta Box', 'textdomain' ),
array( $this, 'render_metabox' ),
'post',
'advanced',
'default'
);
}
/**
* Renders the meta box.
*/
public function render_metabox( $post ) {
// Add nonce for security and authentication.
wp_nonce_field( 'custom_nonce_action', 'custom_nonce' );
}
/**
* Handles saving the meta box.
*
* @param int $post_id Post ID.
* @param WP_Post $post Post object.
* @return null
*/
public function save_metabox( $post_id, $post ) {
// Add nonce for security and authentication.
$nonce_name = isset( $_POST['custom_nonce'] ) ? $_POST['custom_nonce'] : '';
$nonce_action = 'custom_nonce_action';
// Check if nonce is set.
if ( ! isset( $nonce_name ) ) {
return;
}
// Check if nonce is valid.
if ( ! wp_verify_nonce( $nonce_name, $nonce_action ) ) {
return;
}
// Check if user has permissions to save data.
if ( ! current_user_can( 'edit_post', $post_id ) ) {
return;
}
// Check if not an autosave.
if ( wp_is_post_autosave( $post_id ) ) {
return;
}
// Check if not a revision.
if ( wp_is_post_revision( $post_id ) ) {
return;
}
}
}
new WPDocs_Custom_Meta_Box();
?>