wp_send_json_success( mixed $value = null, int $status_code = null, int $flags = 0 ): never

Compatibility

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

Parameters

$valuemixedoptional

Data to encode as JSON, then print and die. Default null.Default: null

$status_codeintoptional

The HTTP status code to output. Default null.Default: null

$flagsintoptional

Options to be passed to json_encode(). Default 0.Default: 0

Return value

never

Code examples

Every example is editable and runs in a real WordPress booted in your browser by WordPress Playground. Press Run, then edit the code: clicking away re-runs it. Nothing is sent anywhere until you do.

$post  = get_post( 2 );
$price = get_post_meta( 2, 'price', true );

wp_send_json_success(
	array(
		'title' => $post->post_title,
		'price' => $price,
	)
);

echo 'This line never runs.';

$post_id = wp_insert_post(
	array(
		'post_title'  => 'Draft created via Ajax',
		'post_status' => 'draft',
		'post_type'   => 'post',
	)
);

wp_send_json_success(
	array( 'id' => $post_id ),
	201,
	JSON_UNESCAPED_SLASHES
);

Common problems and fixes · 4

• Why does my Ajax response come back as HTML wrapped around the JSON instead of clean JSON?
• Why is response.data missing on the client instead of being null?
• Why does code I put after wp_send_json_success() never execute?
• Why does passing a status code do nothing on my site?

Alternatives and related functions

wp_send_json_error

When the Ajax request failed and the response should carry success: false along with error details.

wp_send_json

When the response needs a shape other than {success, data}, since wp_send_json_success is just a thin wrapper around it.

rest_ensure_response

When building a REST API endpoint rather than a classic admin-ajax.php handler.

wp_die

When more control over the die handler or headers is needed than wp_send_json provides.

Performance profile

How much work a call to wp_send_json_success() 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

Moderate

Reads stored settings via get_option(), cached per request but not free on a cold cache.

Scaling

Constant

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

Instructions

12–14

Executed per call on PHP 8.5, depending on the branch taken. The body compiles to 14.

Plugin surface

None

Nothing here hands control to plugin code.

Called by

50

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

What it touches

• optionoption read or writeget_option()one call below wp_send_json_success()

Further down the call graph this can also reach hook, cache, serialize, query and transient. Those are the worst case, several calls deep and usually down an error path, not what a normal call pays.

What one call costs · 1 distinct outcome

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

Uses · 1

• wp_send_json()Sends a JSON response back to an Ajax request.

Used by · 50

• Custom_Background::ajax_background_add()Handles Ajax request for adding custom background context to an attachment.
• Custom_Image_Header::ajax_header_add()Given an attachment ID for a header image, updates its "last used" timestamp to now.
• Custom_Image_Header::ajax_header_crop()Gets attachment uploaded by Media Manager, crops it, then saves it as a new object. Returns JSON-encoded object details.
• Custom_Image_Header::ajax_header_remove()Given an attachment ID for a header image, unsets it as a user-uploaded header image for the active theme.
• WP_Customize_Manager::handle_changeset_trash_request()Handles request to trash a changeset.
• WP_Customize_Manager::handle_dismiss_autosave_or_lock_request()Deletes a given auto-draft changeset or the autosave revision for a given changeset or delete changeset lock.
• WP_Customize_Manager::handle_load_themes_request()Loads themes into the theme browsing/installation UI.
• WP_Customize_Manager::handle_override_changeset_lock_request()Removes changeset lock when take over request is sent via Ajax.
• WP_Customize_Manager::refresh_nonces()Refreshes nonces for the current preview.
• WP_Customize_Manager::save()Handles customize_save WP Ajax request to save/update a changeset.
• WP_Customize_Nav_Menus::ajax_insert_auto_draft_post()Ajax handler for adding a new auto-draft post.
• WP_Customize_Nav_Menus::ajax_load_available_items()Ajax handler for loading available menu items.

Source code

View on Trac ↗View on GitHub ↗

4635function wp_send_json_success( $value = null, $status_code = null, $flags = 0 ) {4636	$response = array( 'success' => true );4637 4638	if ( isset( $value ) ) {4639		$response['data'] = $value;4640	}4641 4642	wp_send_json( $response, $status_code, $flags );4643}

Changelog

Introduced in 3.5.0. One change between 6.7.7 and 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/functions.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.

Corrections

Something wrong on this page? Report it and it gets fixed in the next regeneration.