WordPress功能函数add_option()
wordpress功能函数add_option()，添加一个新的选项。
用法：
add_option( string $option, mixed $value = '', string $deprecated = '', string|bool $autoload = 'yes' )
描述
您不需要序列化值。如果需要对值进行序列化，那么将在将其插入数据库之前对其进行序列化。请记住，资源不能序列化或作为选项添加。
您可以创建没有值的选项，然后稍后更新这些值。现有的选项不会被更新，并且会执行检查以确保你没有添加一个受保护的WordPress选项。注意不要将选项命名为与受保护选项相同的选项。
参数：
$option
(string) (必需) 要添加的选项的名称。预计不会被sql转义。
$value
(mixed) (可选) 选项值。如果是非标量，则必须是可序列化的。预计不会被sql转义。
默认值: ''
$deprecated
(string) (可选) 描述。不习惯了。
默认值: ''
$autoload
(string|bool) (可选) 是否在WordPress启动时加载该选项。默认是启用的。由于遗留原因，接受“no”来禁用。
默认值: 'yes'
返回
(bool)添加该选项时为True，否则为false。
来源：
文件: wp-includes/option.php
function add_option( $option, $value = '', $deprecated = '', $autoload = 'yes' ) {
global $wpdb;
if ( ! empty( $deprecated ) ) {
_deprecated_argument( __FUNCTION__, '2.3.0' );
}
$option = trim( $option );
if ( empty( $option ) ) {
return false;
}
/*
* Until a proper _deprecated_option() function can be introduced,
* redirect requests to deprecated keys to the new, correct ones.
*/
$deprecated_keys = array(
'blacklist_keys' => 'disallowed_keys',
'comment_whitelist' => 'comment_previously_approved',
);
if ( ! wp_installing() && isset( $deprecated_keys[ $option ] ) ) {
_deprecated_argument(
__FUNCTION__,
'5.5.0',
sprintf(
/* translators: 1: Deprecated option key, 2: New option key. */
__( 'The "%1$s" option key has been renamed to "%2$s".' ),
$option,
$deprecated_keys[ $option ]
)
);
return add_option( $deprecated_keys[ $option ], $value, $deprecated, $autoload );
}
wp_protect_special_option( $option );
if ( is_object( $value ) ) {
$value = clone $value;
}
$value = sanitize_option( $option, $value );
// Make sure the option doesn't already exist.
// We can check the 'notoptions' cache before we ask for a DB query.
$notoptions = wp_cache_get( 'notoptions', 'options' );
if ( ! is_array( $notoptions ) || ! isset( $notoptions[ $option ] ) ) {
/** This filter is documented in wp-includes/option.php */
if ( apply_filters( "default_option_{$option}", false, $option, false ) !== get_option( $option ) ) {
return false;
}
}
$serialized_value = maybe_serialize( $value );
$autoload = ( 'no' === $autoload || false === $autoload ) ? 'no' : 'yes';
/**
* Fires before an option is added.
*
* @since 2.9.0
*
* @param string $option Name of the option to add.
* @param mixed $value Value of the option.
*/
do_action( 'add_option', $option, $value );
$result = $wpdb->query( $wpdb->prepare( "INSERT INTO `$wpdb->options` (`option_name`, `option_value`, `autoload`) VALUES (%s, %s, %s) ON DUPLICATE KEY UPDATE `option_name` = VALUES(`option_name`), `option_value` = VALUES(`option_value`), `autoload` = VALUES(`autoload`)", $option, $serialized_value, $autoload ) );
if ( ! $result ) {
return false;
}
if ( ! wp_installing() ) {
if ( 'yes' === $autoload ) {
$alloptions = wp_load_alloptions( true );
$alloptions[ $option ] = $serialized_value;
wp_cache_set( 'alloptions', $alloptions, 'options' );
} else {
wp_cache_set( $option, $serialized_value, 'options' );
}
}
// This option exists now.
$notoptions = wp_cache_get( 'notoptions', 'options' ); // Yes, again... we need it to be fresh.
if ( is_array( $notoptions ) && isset( $notoptions[ $option ] ) ) {
unset( $notoptions[ $option ] );
wp_cache_set( 'notoptions', $notoptions, 'options' );
}
/**
* Fires after a specific option has been added.
*
* The dynamic portion of the hook name, `$option`, refers to the option name.
*
* @since 2.5.0 As "add_option_{$name}"
* @since 3.0.0
*
* @param string $option Name of the option to add.
* @param mixed $value Value of the option.
*/
do_action( "add_option_{$option}", $option, $value );
/**
* Fires after an option has been added.
*
* @since 2.9.0
*
* @param string $option Name of the added option.
* @param mixed $value Value of the option.
*/
do_action( 'added_option', $option, $value );
return true;
}
更新日志：
用户贡献的笔记
（由Codex - 5年前贡献）
基本的例子：
