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action is not described

add_(meta_type)_meta action-hook . WP 3.1.0

Fires immediately before meta of a specific type is added.

The dynamic portion of the hook, $meta_type, refers to the meta object type (comment, post, term, or user).

Usage

add_action( 'add_(meta_type)_meta', 'action_function_name_7390', 10, 3 );
function action_function_name_7390( $object_id, $meta_key, $_meta_value ){
	// action...
}
$object_id(int)
ID of the object metadata is for.
$meta_key(string)
Metadata key.
$_meta_value(mixed)
Metadata value. Serialized if non-scalar.

Changelog

Since 3.1.0 Introduced.

Where the hook is called

add_metadata()
add_(meta_type)_meta
wp-includes/meta.php 101
do_action( "add_{$meta_type}_meta", $object_id, $meta_key, $_meta_value );

Where in WP core the hook is used

Usage not found!