get_option( string $option, mixed $default = false )

Retrieves an option value based on an option name.


Description

If the option does not exist or does not have a value, then the return value will be false. This is useful to check whether you need to install an option and is commonly used during installation of plugin options and to test whether upgrading is required.

If the option was serialized then it will be unserialized when it is returned.

Any scalar values will be returned as strings. You may coerce the return type of a given option by registering an ‘option_$option’ filter callback.


Parameters

$option

(Required) Name of option to retrieve. Expected to not be SQL-escaped.

$default

(Optional) Default value to return if the option does not exist.

Default value: false


Return

(mixed) Value set for the option.


Source

File: wp-includes/option.php

function get_option( $option, $default = false ) {
	global $wpdb;

	$option = trim( $option );
	if ( empty( $option ) )
		return false;

	/**
	 * Filters the value of an existing option before it is retrieved.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * Passing a truthy value to the filter will short-circuit retrieving
	 * the option value, returning the passed value instead.
	 *
	 * @since WP-1.5.0
	 * @since WP-4.4.0 The `$option` parameter was added.
	 * @since WP-4.9.0 The `$default` parameter was added.
	 *
	 *
	 * @param bool|mixed $pre_option The value to return instead of the option value. This differs from
	 *                               `$default`, which is used as the fallback value in the event the option
	 *                               doesn't exist elsewhere in get_option(). Default false (to skip past the
	 *                               short-circuit).
	 * @param string     $option     Option name.
	 * @param mixed      $default    The fallback value to return if the option does not exist.
	 *                               Default is false.
	 */
	$pre = apply_filters( "pre_option_{$option}", false, $option, $default );

	if ( false !== $pre )
		return $pre;

	if ( defined( 'WP_SETUP_CONFIG' ) )
		return false;

	// Distinguish between `false` as a default, and not passing one.
	$passed_default = func_num_args() > 1;

	if ( ! wp_installing() ) {
		// prevent non-existent options from triggering multiple queries
		$notoptions = wp_cache_get( 'notoptions', 'options' );
		if ( isset( $notoptions[ $option ] ) ) {
			/**
			 * Filters the default value for an option.
			 *
			 * The dynamic portion of the hook name, `$option`, refers to the option name.
			 *
			 * @since WP-3.4.0
			 * @since WP-4.4.0 The `$option` parameter was added.
			 * @since WP-4.7.0 The `$passed_default` parameter was added to distinguish between a `false` value and the default parameter value.
			 *
			 * @param mixed  $default The default value to return if the option does not exist
			 *                        in the database.
			 * @param string $option  Option name.
			 * @param bool   $passed_default Was `get_option()` passed a default value?
			 */
			return apply_filters( "default_option_{$option}", $default, $option, $passed_default );
		}

		$alloptions = wp_load_alloptions();

		if ( isset( $alloptions[$option] ) ) {
			$value = $alloptions[$option];
		} else {
			$value = wp_cache_get( $option, 'options' );

			if ( false === $value ) {
				$row = $wpdb->get_row( $wpdb->prepare( "SELECT option_value FROM $wpdb->options WHERE option_name = %s LIMIT 1", $option ) );

				// Has to be get_row instead of get_var because of funkiness with 0, false, null values
				if ( is_object( $row ) ) {
					$value = $row->option_value;
					wp_cache_add( $option, $value, 'options' );
				} else { // option does not exist, so we must cache its non-existence
					if ( ! is_array( $notoptions ) ) {
						 $notoptions = array();
					}
					$notoptions[$option] = true;
					wp_cache_set( 'notoptions', $notoptions, 'options' );

					/** This filter is documented in wp-includes/option.php */
					return apply_filters( "default_option_{$option}", $default, $option, $passed_default );
				}
			}
		}
	} else {
		$suppress = $wpdb->suppress_errors();
		$row = $wpdb->get_row( $wpdb->prepare( "SELECT option_value FROM $wpdb->options WHERE option_name = %s LIMIT 1", $option ) );
		$wpdb->suppress_errors( $suppress );
		if ( is_object( $row ) ) {
			$value = $row->option_value;
		} else {
			/** This filter is documented in wp-includes/option.php */
			return apply_filters( "default_option_{$option}", $default, $option, $passed_default );
		}
	}

	// If home is not set use siteurl.
	if ( 'home' == $option && '' == $value )
		return get_option( 'siteurl' );

	if ( in_array( $option, array('siteurl', 'home', 'category_base', 'tag_base') ) )
		$value = untrailingslashit( $value );

	/**
	 * Filters the value of an existing option.
	 *
	 * The dynamic portion of the hook name, `$option`, refers to the option name.
	 *
	 * @since WP-1.5.0 As 'option_' . $setting
	 * @since WP-3.0.0
	 * @since WP-4.4.0 The `$option` parameter was added.
	 *
	 * @param mixed  $value  Value of the option. If stored serialized, it will be
	 *                       unserialized prior to being returned.
	 * @param string $option Option name.
	 */
	return apply_filters( "option_{$option}", maybe_unserialize( $value ), $option );
}


Changelog

Changelog
Version Description
WP-1.5.0 Introduced.