public function delete($useWhere = FALSE)
 {
     $id = $this->id;
     $result = parent::delete($useWhere);
     try {
         $custom_params['custom_group_id'] = civicrm_api3('CustomGroup', 'getvalue', array('name' => 'myemma', 'return' => 'id'));
         $custom_params['name'] = 'my_emmma_' . $id;
         $custom_field = civicrm_api3('CustomField', 'getsingle', $custom_params);
         civicrm_api3('CustomField', 'delete', array('id' => $custom_field['id']));
     } catch (Exception $e) {
         //do nothing
     }
     return $result;
 }
 /**
  * Returns the list of fields that can be exported
  *
  * @param bool $prefix
  *
  * @return array
  */
 static function &export($prefix = false)
 {
     if (!self::$_export) {
         self::$_export = array();
         $fields = self::fields();
         foreach ($fields as $name => $field) {
             if (CRM_Utils_Array::value('export', $field)) {
                 if ($prefix) {
                     self::$_export['my_emma_account'] =& $fields[$name];
                 } else {
                     self::$_export[$name] =& $fields[$name];
                 }
             }
         }
     }
     return self::$_export;
 }