wp_register_sidebar_widget( int|string $id, string $name, callable $output_callback, array $options = array(), mixed $params )

Description

Compatibility

Present in every tracked release (6.7.7 to 7.1.0), and compiles on PHP 7.4 through 8.6-dev.

Parameters

$idint|string

Widget ID.

$namestring

Widget display title.

$output_callbackcallable

Run when widget is called.

$optionsarrayoptional

An array of supplementary widget options for the instance.Default: array()

• $classnamestringdefault: is a shortened version of the output callback name

  Class name for the widget's HTML container.

• $descriptionstring

  Widget description for display in the widget administration panel and/or theme.

• $show_instance_in_restbool

  Whether to show the widget's instance settings in the REST API. Only available for WP_Widget based widgets.

$paramsmixed

Optional additional parameters to pass to the callback function when it's called.

Performance profile

How much work a call to wp_register_sidebar_widget() does, and what it touches: the algorithmic scaling, the Zend instruction count per call across PHP versions, the hooks it hands control to, and the core code that calls it. Measured from the compiled opcodes, not a stopwatch, so every number is identical on any machine running the same PHP version, and every function in core is ranked by cost.

Cost class

Trivial

Touches nothing outside its own arguments.

Scaling

Constant

No loop in the body: the same number of instructions runs whatever you pass in.

Instructions

17–59

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 64.

Plugin surface

1 hook

Third-party callbacks on 'wp_register_sidebar_widget' run inside this call, and their cost is not bounded by anything here.

Called by

3

3 places in core call this, so the cost is paid more often than your own code shows.

What it touches

• hookthird-party callbacksdo_action()called directly

What one call costs · 10 distinct outcomes

One number would be a lie: the work depends on which branch runs. These are every distinct cost wp_register_sidebar_widget() can have, taken from its control-flow graph on PHP 8.5.

Hooks and filters fired · 1

One hook fires while wp_register_sidebar_widget() runs, in this order:

1. 1
   do_action( wp_register_sidebar_widget )actionline 432 (+36 into the body)

   Fires once for each registered widget.

Uses · 4

• _get_widget_id_base()Retrieves the widget ID base value.
• wp_parse_args()Merges user defined arguments into defaults array.
• did_action()Retrieves the number of times an action has been fired during the current request.
• do_action()Calls the callback functions that have been added to an action hook.

Used by · 3

• WP_Widget::_register_one()Registers an instance of the widget class.
• register_sidebar_widget()Register widget for sidebar with backward compatibility.
• wp_unregister_sidebar_widget()Remove widget from sidebar.

Source code

View on Trac ↗View on GitHub ↗

396function wp_register_sidebar_widget( $id, $name, $output_callback, $options = array(), ...$params ) {397	global $wp_registered_widgets, $wp_registered_widget_controls, $wp_registered_widget_updates, $_wp_deprecated_widgets_callbacks;398 399	$id = strtolower( $id );400 401	if ( empty( $output_callback ) ) {402		unset( $wp_registered_widgets[ $id ] );403		return;404	}405 406	$id_base = _get_widget_id_base( $id );407	if ( in_array( $output_callback, $_wp_deprecated_widgets_callbacks, true ) && ! is_callable( $output_callback ) ) {408		unset( $wp_registered_widget_controls[ $id ] );409		unset( $wp_registered_widget_updates[ $id_base ] );410		return;411	}412 413	$defaults = array( 'classname' => $output_callback );414	$options  = wp_parse_args( $options, $defaults );415	$widget   = array(416		'name'     => $name,417		'id'       => $id,418		'callback' => $output_callback,419		'params'   => $params,420	);421	$widget   = array_merge( $widget, $options );422 423	if ( is_callable( $output_callback ) && ( ! isset( $wp_registered_widgets[ $id ] ) || did_action( 'widgets_init' ) ) ) {424 425		/**426		 * Fires once for each registered widget.427		 *428		 * @since 3.0.0429		 *430		 * @param array $widget An array of default widget arguments.431		 */432		do_action( 'wp_register_sidebar_widget', $widget );433		$wp_registered_widgets[ $id ] = $widget;434	}435}

Changelog

Introduced in 2.2.0. Unchanged from 6.7.7 through 7.1.0.

1. 6.7.7
2. 6.8.8
3. 6.9.7
4. 7.0.4
5. 7.1.0

Signature, return type and hooks compared across 5 parsed releases.

About this page

Parsed data

Generated from the wordpress-develop 7.1.0 tag, from src/wp-includes/widgets.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

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