How can I remove specific custom post meta from the “Custom Fields” fieldset?

Question

I've created a custom meta box to handle certain custom post meta fields and I don't want the clutter of having these custom fields duplicated down in the "Custom Fields" area.

How can I remove specific custom post meta from the "Custom Fields" fieldset?

Answer 1

To hide a custom field from the "Custom Fields" section, prefix it with an underscore. So add_post_meta($id, 'name', 'value'); becomes add_post_meta($id, '_name', 'value');.

Here's a good reference for backup:

• How to Hide Your Plugin's Custom Fields

Answer 2

You can hook into the is_protected_meta filter and return true for any custom field you want to hide.

add_filter('is_protected_meta', 'my_is_protected_meta_filter', 10, 2);
function my_is_protected_meta_filter($protected, $meta_key) {
    return $meta_key == 'meta-name' ? true : $protected;
}