Reply To: ACF Form Unique Value Validation

• John Huebner

• December 14, 2023 at 7:36 am

The values isset($_POST[‘post_ID’] or $_POST[‘post_id’] are not set on the front end when creating a new post with acf_form().

You’re going to have to alter the code to account for not having a post ID

add_filter('acf/validate_value/name=inventory_id', 'acf_unique_value_field', 10, 4);
  function acf_unique_value_field($valid, $value, $field, $input) {
    if (!$valid) {
      return $valid;
    }
    if (isset($_POST['post_ID'])) {
      $post_id = intval($_POST['post_ID']);
    } elseif (isset($_POST['post_id'])) {
      $post_id = intval($_POST['post_id']);
    } else {
      $post_id = false;
    }
    $post_type = get_post_type($post_id);
    $field_name = $field['name'];
    $args = array(
      'post_type' => $post_type,
      'post_status' => 'publish, draft, trash',
      'meta_query' => array(
        array(
          'key' => $field_name,
          'value' => $value
        )
      )
    );
    if (!empty($post_id) {
      $args['post__not_in'] = array($post_id);
    }
    $query = new WP_Query($args);
    if (count($query->posts)){
      return 'This Value is not Unique. Please enter a unique '.$field['label'];
    }
    return true;
  }