wp_json_encode()

Function: Encode a variable into JSON, with some sanity checks.

Source: wp-includes/functions.php:3127

wp_send_json_error()

Function: Send a JSON response back to an Ajax request, indicating failure.

Source: wp-includes/functions.php:3353

Function: Kill ClassicPress execution and display HTML message with error message.

Source: wp-includes/functions.php:2806

Method: Ajax handler for adding custom background context to an attachment.

Source: wp-admin/custom-background.php:497

Filter Hook: Filters the caption text.

Source: wp-admin/includes/media.php:188

Function: Ajax handler for destroying multiple open sessions for a user.

Source: wp-admin/includes/ajax-actions.php:3148

Filter Hook: Filters the title of the default page template displayed in the drop-down.

Source: wp-admin/includes/meta-boxes.php:893

Action Hook: Fires before an autosave is stored.

Source: wp-admin/includes/post.php:1747

Method: Deactivates a plugin before it is upgraded.

Source: wp-admin/includes/class-plugin-upgrader.php:395

Function: Print JavaScript in the header on the Network Settings screen.

Source: wp-admin/includes/ms.php:869