支付的时候的参数校验

public function sign(array $param, string $secret): string
    {
        unset($param['sign']);
        if (!isset(
            $param['member_id'],
            $param['client_ip'],
            $param['nonce_str'],
            $param['out_trade_no'],
            $param['time_start'],
            $param['time_expire'],
            $param['total_amount']
        )) {
            return '';
        }

        foreach ($param as $k => $v) {
            if (!is_scalar($v) || '' === ($v = trim((string)$v))) {
                unset($param[$k]);
            }
        }

        ksort($param);
        return sha1(md5(http_build_query($param)) . md5($secret));
    }


 public function verifyPassword(int $memberId, string $password): bool
    {
        // 密码必须使用 sha1 进行加密传递，sha1 长度为 40
        if (strlen($password) !== 40) {
            return false;
        }

        if (false === ($account = $this->findAccount($memberId))) {
            return false;
        }

        return $this->encryptPassword($password, $account['salt']) === $account['password'];
    }

public function encryptPassword(string $password, string$salt): string
    {
        return md5(md5($password) . $salt);
    }