/** * Generate unique 'ono' + 10 digitals number * Probability in duplicate number 0.1 ~ 0.5% * @return string */ public static function generateUniqueCustomersCode() { $customersModel = new CustomersModel(); $result = 1; $customerCode = ''; while (!empty($result)) { $ranNumber = self::generateUniqueDigital(); if (is_numeric($ranNumber) && isset($ranNumber)) { $customerCode = 'KH' . $ranNumber; $result = $customersModel->checkCustomerCode($customerCode); } } return $customerCode; }