settings_fields() │ WP 2.7.0

Output nonce, action, and option_page fields for a settings page.

Uses: wp_nonce_field()

No Hooks.

Return

null. Nothing.

Usage

settings_fields( $option_group );
$option_group(string) (required)
A settings group name. This should match the group name used in register_setting().

Changelog

Since 2.7.0 Introduced.

Code of settings_fields() WP 6.0

wp-admin/includes/plugin.php 
function settings_fields( $option_group ) {
	echo "<input type='hidden' name='option_page' value='" . esc_attr( $option_group ) . "' />";
	echo '<input type="hidden" name="action" value="update" />';
	wp_nonce_field( "$option_group-options" );
}

Settings API