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This action runs before a field group is saved.

do_action( 'rwmb_before_save_post', $object_id );

It takes 1 parameter: current object ID.


Although the action name is rwmb_before_save_post, it applies to all object types, including term, user, or setting. We keep the name for historical reasons.

To run this action for a specific field group, use a variation of this action:

do_action( "rwmb_{$field_group_id}_before_save_post", $object_id );


Changing a field value before saving:

add_action( 'rwmb_event-details_before_save_post', function() {
$_POST['location'] = 'United States';
} );

Changing a field value based on another field value:

add_action( 'rwmb_event-details_before_save_post', function() {
if ( $_POST['event_type'] === 'festival' ) {
$_POST['event_start_time'] = '09:00';
$_POST['event_end_time'] = '17:00';
} );