Using WordPress ‘register_setting()’ PHP function

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The register_setting() WordPress PHP function registers a setting and its data.

Usage

register_setting( $option_group, $option_name, $args );

Example:

register_setting( 'general', 'custom_option_name', array( 'sanitize_callback' => 'sanitize_text_field' ) );

Parameters

  • $option_group (string): A settings group name. Default allowed option key names include ‘general’, ‘discussion’, ‘media’, ‘reading’, ‘writing’, and ‘options’.
  • $option_name (string): The name of an option to sanitize and save.
  • $args (array) – Optional: Data used to describe the setting when registered. Includes:
    • type (string): The type of data associated with this setting. Valid values are ‘string’, ‘boolean’, ‘integer’, ‘number’, ‘array’, and ‘object’.
    • description (string): A description of the data attached to this setting.
    • sanitize_callback (callable): A callback function that sanitizes the option’s value.
    • show_in_rest (bool|array): Whether data associated with this setting should be included in the REST API.
    • default (mixed): Default value when calling get_option().

More information

See WordPress Developer Resources: register_setting()

Examples

Register a simple text field setting

Registers a new setting called ‘custom_text_field’ in the ‘general’ group.

function myplugin_register_settings() {
   register_setting( 'general', 'custom_text_field', array( 'sanitize_callback' => 'sanitize_text_field' ) );
}
add_action( 'admin_init', 'myplugin_register_settings' );

Register a number field setting

Registers a new setting called ‘custom_number_field’ in the ‘general’ group.

function myplugin_register_settings() {
   register_setting( 'general', 'custom_number_field', array( 'sanitize_callback' => 'absint' ) );
}
add_action( 'admin_init', 'myplugin_register_settings' );

Register a checkbox setting

Registers a new setting called ‘custom_checkbox’ in the ‘discussion’ group.

function myplugin_register_settings() {
   register_setting( 'discussion', 'custom_checkbox', array( 'sanitize_callback' => 'myplugin_sanitize_checkbox' ) );
}

function myplugin_sanitize_checkbox( $input ) {
   return ( isset( $input ) ? true : false );
}
add_action( 'admin_init', 'myplugin_register_settings' );

Register a setting with a custom sanitization function

Registers a new setting called ‘custom_setting’ in the ‘writing’ group with a custom sanitization function.

function myplugin_register_settings() {
   register_setting( 'writing', 'custom_setting', array( 'sanitize_callback' => 'myplugin_sanitize_custom_setting' ) );
}

function myplugin_sanitize_custom_setting( $input ) {
   // Perform custom sanitization on $input
   return $sanitized_input;
}
add_action( 'admin_init', 'myplugin_register_settings' );

Register a setting with REST API support

Registers a new setting called ‘custom_rest_setting’ in the ‘media’ group with REST API support.

function myplugin_register_settings() {
   register_setting( 'media', 'custom_rest_setting', array( 'type' => 'string', 'sanitize_callback' => 'sanitize_text_field', '