private function replace_cfield_shortcodes($tag_value)
 {
     $replacement = '';
     if (isset($tag_value)) {
         $user_id = (int) $this->receiver->user_id;
         $field_id = (int) $tag_value;
         $field_user = new WJ_FieldUser();
         $field_user->set(array('user_id' => $user_id, 'field_id' => $field_id));
         $value = $field_user->value();
         // If we don't have a value, we return the empty string.
         if (isset($value)) {
             // Check if the field value needs formatting output.
             switch ($field_user->field->type) {
                 case 'checkbox':
                     if ($value == 1) {
                         $value = "Yes";
                     } else {
                         $value = "No";
                     }
                     break;
                 case 'date':
                     $value = date('F j, Y', $value);
                     break;
                 default:
                     break;
             }
             $replacement = $value;
         } else {
             $replacement = '';
         }
     }
     return $replacement;
 }