What is WordPress Hook: add_{$meta_type}_meta
The add_{$meta_type}_meta hook in WordPress is used to perform actions when adding metadata of a specific type to a post, term, user, or comment. This hook allows developers to execute custom functions before or after the metadata is added to the database.
Understanding the Hook: add_{$meta_type}_meta
The add_{$meta_type}_meta hook is located within the wp-includes/meta.php file in WordPress. It is specifically used when adding metadata of a certain type, such as post meta, term meta, user meta, or comment meta. This hook provides a way to modify or perform actions related to the metadata before it is saved to the database.
Hook Parameters (if applicable): add_{$meta_type}_meta
The add_{$meta_type}_meta hook accepts parameters such as $meta_id, $object_id, $meta_key, $meta_value, and $unique. These parameters allow developers to access and manipulate the metadata being added, providing flexibility and customization options.
Hook Doesn’t Work: add_{$meta_type}_meta
If the add_{$meta_type}_meta hook doesn’t work as expected, it could be due to incorrect usage or conflicts with other plugins or themes. To troubleshoot, developers should check for any syntax errors in their code, ensure that the hook is being called at the appropriate time, and deactivate other plugins to identify any conflicts.
Best Practices & Usage Notes (if applicable): add_{$meta_type}_meta
When using the add_{$meta_type}_meta hook, it is important to consider the potential impact on performance, as executing custom functions before or after adding metadata can affect the overall processing time. Developers should also be mindful of any limitations or restrictions related to the specific type of metadata being added, and test their code thoroughly to ensure compatibility with different scenarios.
Usage Example: add_{$meta_type}_meta
“`php
function custom_meta_function( $meta_id, $object_id, $meta_key, $meta_value, $unique ) {
// Perform custom actions when adding metadata
}
add_action( ‘add_post_meta’, ‘custom_meta_function’, 10, 5 );
“`
In this example, the add_post_meta hook is used to call the custom_meta_function when post metadata is being added, allowing developers to execute their own code before or after the metadata is saved.