How to use delete_meta_type_metadata filter in WordPress

delete_meta_type_metadata filter

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.

To use delete_meta_type_metadata filter, first, you have to register it using add_filter. You can write this code into the functions.php of your activated theme or in a custom WordPress Plugin.

We at WePlugins always prefer to create a custom WordPress Plugin while using hooks so nothing breaks when you update your WordPress Theme in the future.

In the below live example, we have defined a function modify_delete_meta_type_metadata_defaults which takes 5 parameters and we registered using add_filter. The first parameter delete_meta_type_metadata is the name of the hook, the second parameter modify_delete_meta_type_metadata_defaults is the name of the function which needs to be called, the third parameter is the priority of calling the hook if the same hook is used multiple times and the last parameter is the number of arguments (if any) to be passed in the registered function.

Sometimes, you have to remove a registered hook so you can use remove_filter to remove delete_meta_type_metadata filter.

Parameters

Below are the 5 parameters required to use this hook.

• $delete : (null|bool) Whether to allow metadata deletion of the given type.
• $object_id : (int) ID of the object metadata is for.
• $meta_key : (string) Metadata key.
• $meta_value : (mixed) Metadata value. Must be serializable if non-scalar.
• $delete_all : (bool) Whether to delete the matching metadata entries for all objects, ignoring the specified $object_id. Default false.

Live Example

Example 1: Basic Hook Usage

Below is an example of how you can use this hook.

    function weplugins_modify_delete_meta_type_metadata_defaults($delete, $object_id, $meta_key, $meta_value, $delete_all) { 
        // Update the $delete variable according to your website requirements and return this variable.
        // You can modify the $delete variable conditionally too if you want.
        return $delete; 
    }
    // add the filter
    add_filter( "delete_meta_type_metadata", "weplugins_modify_delete_meta_type_metadata_defaults", 10, 5 );
    

Example 2: Conditional Metadata Deletion

In this example, we’ll conditionally modify the $delete variable.

    function weplugins_conditional_delete_meta_type_metadata($delete, $object_id, $meta_key, $meta_value, $delete_all) { 
        // Allow deletion only if the meta_key is 'custom_key'
        if ($meta_key == 'custom_key') {
            $delete = true;
        }
        return $delete; 
    }
    // add the filter
    add_filter( "delete_meta_type_metadata", "weplugins_conditional_delete_meta_type_metadata", 10, 5 );
    

Example 3: Removing the Hook

To remove a hook callback, use the example below.

    remove_filter( "delete_meta_type_metadata", "weplugins_modify_delete_meta_type_metadata_defaults", 10, 5 );
    

Please make sure to provide the same callback function name, priority, and number of arguments while removing the hook callback.

Contact Us

If you need any customization or are having trouble using this hook, please Contact Us, and we’d be happy to assist you.