Adds metadata for the specified object.
Parameters
$meta_type
stringrequired- Type of object metadata is for. Accepts
'post'
,'comment'
,'term'
,'user'
, or any other object type with an associated meta table. $object_id
intrequired- ID of the object metadata is for.
$meta_key
stringrequired- Metadata key.
$meta_value
mixedrequired- Metadata value. Must be serializable if non-scalar.
$unique
booloptional- Whether the specified metadata key should be unique for the object.
If true, and the object already has a value for the specified metadata key, no change will be made.Default:
false
Source
function add_metadata( $meta_type, $object_id, $meta_key, $meta_value, $unique = false ) {
global $wpdb;
if ( ! $meta_type || ! $meta_key || ! is_numeric( $object_id ) ) {
return false;
}
$object_id = absint( $object_id );
if ( ! $object_id ) {
return false;
}
$table = _get_meta_table( $meta_type );
if ( ! $table ) {
return false;
}
$meta_subtype = get_object_subtype( $meta_type, $object_id );
$column = sanitize_key( $meta_type . '_id' );
// expected_slashed ($meta_key)
$meta_key = wp_unslash( $meta_key );
$meta_value = wp_unslash( $meta_value );
$meta_value = sanitize_meta( $meta_key, $meta_value, $meta_type, $meta_subtype );
/**
* Short-circuits adding metadata of a specific type.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
* Returning a non-null value will effectively short-circuit the function.
*
* Possible hook names include:
*
* - `add_post_metadata`
* - `add_comment_metadata`
* - `add_term_metadata`
* - `add_user_metadata`
*
* @since 3.1.0
*
* @param null|bool $check Whether to allow adding metadata for the given type.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $meta_value Metadata value. Must be serializable if non-scalar.
* @param bool $unique Whether the specified meta key should be unique for the object.
*/
$check = apply_filters( "add_{$meta_type}_metadata", null, $object_id, $meta_key, $meta_value, $unique );
if ( null !== $check ) {
return $check;
}
if ( $unique && $wpdb->get_var(
$wpdb->prepare(
"SELECT COUNT(*) FROM $table WHERE meta_key = %s AND $column = %d",
$meta_key,
$object_id
)
) ) {
return false;
}
$_meta_value = $meta_value;
$meta_value = maybe_serialize( $meta_value );
/**
* Fires immediately before meta of a specific type is added.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `add_post_meta`
* - `add_comment_meta`
* - `add_term_meta`
* - `add_user_meta`
*
* @since 3.1.0
*
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action( "add_{$meta_type}_meta", $object_id, $meta_key, $_meta_value );
$result = $wpdb->insert(
$table,
array(
$column => $object_id,
'meta_key' => $meta_key,
'meta_value' => $meta_value,
)
);
if ( ! $result ) {
return false;
}
$mid = (int) $wpdb->insert_id;
wp_cache_delete( $object_id, $meta_type . '_meta' );
/**
* Fires immediately after meta of a specific type is added.
*
* The dynamic portion of the hook name, `$meta_type`, refers to the meta object type
* (post, comment, term, user, or any other type with an associated meta table).
*
* Possible hook names include:
*
* - `added_post_meta`
* - `added_comment_meta`
* - `added_term_meta`
* - `added_user_meta`
*
* @since 2.9.0
*
* @param int $mid The meta ID after successful update.
* @param int $object_id ID of the object metadata is for.
* @param string $meta_key Metadata key.
* @param mixed $_meta_value Metadata value.
*/
do_action( "added_{$meta_type}_meta", $mid, $object_id, $meta_key, $_meta_value );
return $mid;
}
Hooks
- do_action( “added_{$meta_type}_meta”,
int $mid ,int $object_id ,string $meta_key ,mixed $_meta_value ) Fires immediately after meta of a specific type is added.
- do_action( “add_{$meta_type}_meta”,
int $object_id ,string $meta_key ,mixed $_meta_value ) Fires immediately before meta of a specific type is added.
- apply_filters( “add_{$meta_type}_metadata”,
null|bool $check ,int $object_id ,string $meta_key ,mixed $meta_value ,bool $unique ) Short-circuits adding metadata of a specific type.
Changelog
Version | Description |
---|---|
2.9.0 | Introduced. |
Example:
Add an additional meta value for comments. Here location is the meta key $location is the variable holds its value.