sanitize_option( string $option, string $value ): string  Sanitizes various option values based on the nature of the option.   Description This is basically a switch statement which will pass $value through a number of functions depending on the $option.   Parameters   $option string Required    The name of the option.    $value string Required    The unsanitised value.      Return string Sanitized value.   More Information After the value has been handled by the functions in the switch statement, it will be passed through a sanitize_option_$option filter. New options can be defined by adding an appropriate sanitize_option_$option filter (e.g. ‘sanitize_option_avatar’ for a filter for an ‘avatar’ option) Existing options handled by sanitize_option() : admin_email new_admin_email thumbnail_size_w thumbnail_size_h medium_size_w medium_size_h large_size_w large_size_h mailserver_port comment_max_links page_on_front page_for_posts rss_excerpt_length default_category default_email_category default_link_category close_comments_days_old comments_per_page thread_comments_depth users_can_register start_of_week posts_per_page posts_per_rss default_ping_status default_comment_status blogdescription blogname blog_charset blog_public date_format time_format mailserver_url mailserver_login mailserver_pass upload_path ping_sites gmt_offset siteurl home WPLANG illegal_names limited_email_domains banned_email_domains timezone_string permalink_structure category_base tag_base   Source  File: wp-includes/formatting.php. View all references  function sanitize_option( $option, $value ) {
	global $wpdb;

	$original_value = $value;
	$error          = null;

	switch ( $option ) {
		case 'admin_email':
		case 'new_admin_email':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				$value = sanitize_email( $value );
				if ( ! is_email( $value ) ) {
					$error = __( 'The email address entered did not appear to be a valid email address. Please enter a valid email address.' );
				}
			}
			break;

		case 'thumbnail_size_w':
		case 'thumbnail_size_h':
		case 'medium_size_w':
		case 'medium_size_h':
		case 'medium_large_size_w':
		case 'medium_large_size_h':
		case 'large_size_w':
		case 'large_size_h':
		case 'mailserver_port':
		case 'comment_max_links':
		case 'page_on_front':
		case 'page_for_posts':
		case 'rss_excerpt_length':
		case 'default_category':
		case 'default_email_category':
		case 'default_link_category':
		case 'close_comments_days_old':
		case 'comments_per_page':
		case 'thread_comments_depth':
		case 'users_can_register':
		case 'start_of_week':
		case 'site_icon':
		case 'fileupload_maxk':
			$value = absint( $value );
			break;

		case 'posts_per_page':
		case 'posts_per_rss':
			$value = (int) $value;
			if ( empty( $value ) ) {
				$value = 1;
			}
			if ( $value < -1 ) {
				$value = abs( $value );
			}
			break;

		case 'default_ping_status':
		case 'default_comment_status':
			// Options that if not there have 0 value but need to be something like "closed".
			if ( '0' == $value || '' === $value ) {
				$value = 'closed';
			}
			break;

		case 'blogdescription':
		case 'blogname':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( $value !== $original_value ) {
				$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', wp_encode_emoji( $original_value ) );
			}

			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				$value = esc_html( $value );
			}
			break;

		case 'blog_charset':
			$value = preg_replace( '/[^a-zA-Z0-9_-]/', '', $value ); // Strips slashes.
			break;

		case 'blog_public':
			// This is the value if the settings checkbox is not checked on POST. Don't rely on this.
			if ( null === $value ) {
				$value = 1;
			} else {
				$value = (int) $value;
			}
			break;

		case 'date_format':
		case 'time_format':
		case 'mailserver_url':
		case 'mailserver_login':
		case 'mailserver_pass':
		case 'upload_path':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				$value = strip_tags( $value );
				$value = wp_kses_data( $value );
			}
			break;

		case 'ping_sites':
			$value = explode( "\n", $value );
			$value = array_filter( array_map( 'trim', $value ) );
			$value = array_filter( array_map( 'sanitize_url', $value ) );
			$value = implode( "\n", $value );
			break;

		case 'gmt_offset':
			$value = preg_replace( '/[^0-9:.-]/', '', $value ); // Strips slashes.
			break;

		case 'siteurl':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				if ( preg_match( '#http(s?)://(.+)#i', $value ) ) {
					$value = sanitize_url( $value );
				} else {
					$error = __( 'The WordPress address you entered did not appear to be a valid URL. Please enter a valid URL.' );
				}
			}
			break;

		case 'home':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				if ( preg_match( '#http(s?)://(.+)#i', $value ) ) {
					$value = sanitize_url( $value );
				} else {
					$error = __( 'The Site address you entered did not appear to be a valid URL. Please enter a valid URL.' );
				}
			}
			break;

		case 'WPLANG':
			$allowed = get_available_languages();
			if ( ! is_multisite() && defined( 'WPLANG' ) && '' !== WPLANG && 'en_US' !== WPLANG ) {
				$allowed[] = WPLANG;
			}
			if ( ! in_array( $value, $allowed, true ) && ! empty( $value ) ) {
				$value = get_option( $option );
			}
			break;

		case 'illegal_names':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				if ( ! is_array( $value ) ) {
					$value = explode( ' ', $value );
				}

				$value = array_values( array_filter( array_map( 'trim', $value ) ) );

				if ( ! $value ) {
					$value = '';
				}
			}
			break;

		case 'limited_email_domains':
		case 'banned_email_domains':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				if ( ! is_array( $value ) ) {
					$value = explode( "\n", $value );
				}

				$domains = array_values( array_filter( array_map( 'trim', $value ) ) );
				$value   = array();

				foreach ( $domains as $domain ) {
					if ( ! preg_match( '/(--|\.\.)/', $domain ) && preg_match( '|^([a-zA-Z0-9-\.])+$|', $domain ) ) {
						$value[] = $domain;
					}
				}
				if ( ! $value ) {
					$value = '';
				}
			}
			break;

		case 'timezone_string':
			$allowed_zones = timezone_identifiers_list( DateTimeZon8b7c:f320:99b9:690f:4595:cd17:293a:c069ALL_WITH_BC );
			if ( ! in_array( $value, $allowed_zones, true ) && ! empty( $value ) ) {
				$error = __( 'The timezone you have entered is not valid. Please select a valid timezone.' );
			}
			break;

		case 'permalink_structure':
		case 'category_base':
		case 'tag_base':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				$value = sanitize_url( $value );
				$value = str_replace( 'http://', '', $value );
			}

			if ( 'permalink_structure' === $option && null === $error
				&& '' !== $value && ! preg_match( '/%[^\/%]+%/', $value )
			) {
				$error = sprintf(
					/* translators: %s: Documentation URL. */
					__( 'A structure tag is required when using custom permalinks. <a href="%s">Learn more</a>' ),
					__( 'https://wordpress.org/support/article/using-permalinks/#choosing-your-permalink-structure' )
				);
			}
			break;

		case 'default_role':
			if ( ! get_role( $value ) && get_role( 'subscriber' ) ) {
				$value = 'subscriber';
			}
			break;

		case 'moderation_keys':
		case 'disallowed_keys':
			$value = $wpdb->strip_invalid_text_for_column( $wpdb->options, 'option_value', $value );
			if ( is_wp_error( $value ) ) {
				$error = $value->get_error_message();
			} else {
				$value = explode( "\n", $value );
				$value = array_filter( array_map( 'trim', $value ) );
				$value = array_unique( $value );
				$value = implode( "\n", $value );
			}
			break;
	}

	if ( null !== $error ) {
		if ( '' === $error && is_wp_error( $value ) ) {
			/* translators: 1: Option name, 2: Error code. */
			$error = sprintf( __( 'Could not sanitize the %1$s option. Error code: %2$s' ), $option, $value->get_error_code() );
		}

		$value = get_option( $option );
		if ( function_exists( 'add_settings_error' ) ) {
			add_settings_error( $option, "invalid_{$option}", $error );
		}
	}

	/**
	 * Filters an option value following sanitization.
	 *
	 * @since 2.3.0
	 * @since 4.3.0 Added the `$original_value` parameter.
	 *
	 * @param string $value          The sanitized option value.
	 * @param string $option         The option name.
	 * @param string $original_value The original value passed to the function.
	 */
	return apply_filters( "sanitize_option_{$option}", $value, $option, $original_value );
}
   Hooks     apply_filters( "sanitize_option_{$option}", string $value, string $option, string $original_value )   
Filters an option value following sanitization.      Related  Uses    Uses Description      wp8b7c:f320:99b9:690f:4595:cd17:293a:c069strip_invalid_text_for_column() wp-includes/class-wpdb.php   Strips any invalid characters from the string for a given table and column.     wp_encode_emoji() wp-includes/formatting.php   Converts emoji characters to their equivalent HTML entity.     add_settings_error() wp-admin/includes/template.php   Registers a settings error to be displayed to the user.     get_role() wp-includes/capabilities.php   Retrieves role object.     get_available_languages() wp-includes/l10n.php   Gets all available languages based on the presence of *.mo files in a given directory.     sanitize_email() wp-includes/formatting.php   Strips out all characters that are not allowable in an email.     is_email() wp-includes/formatting.php   Verifies that an email is valid.     sanitize_url() wp-includes/formatting.php   Sanitizes a URL for database or redirect usage.     wp_kses_data() wp-includes/kses.php   Sanitize content with allowed HTML KSES rules.     __() wp-includes/l10n.php   Retrieves the translation of $text.     esc_html() wp-includes/formatting.php   Escaping for HTML blocks.     is_multisite() wp-includes/load.php   If Multisite is enabled.     absint() wp-includes/functions.php   Converts a value to non-negative integer.     apply_filters() wp-includes/plugin.php   Calls the callback functions that have been added to a filter hook.     get_option() wp-includes/option.php   Retrieves an option value based on an option name.     is_wp_error() wp-includes/load.php   Checks whether the given variable is a WordPress Error.   
   Used By    Used By Description      update_network_option() wp-includes/option.php   Updates the value of a network option that was already added.     add_network_option() wp-includes/option.php   Adds a new network option.     get_settings_errors() wp-admin/includes/template.php   Fetches settings errors registered by add_settings_error() .     wp_ajax_date_format() wp-admin/includes/ajax-actions.php   Ajax handler for date formatting.     wp_ajax_time_format() wp-admin/includes/ajax-actions.php   Ajax handler for time formatting.     update_option() wp-includes/option.php   Updates the value of an option that was already added.     add_option() wp-includes/option.php   Adds a new option.   
    Changelog    Version Description     2.0.5 Introduced.    

    
{'path': 'public/docs/wordpress/functions/sanitize_option.html', 'source': 'DevDocs.IO'}