let vc = AuthenticationViewController()
vc.claimShopData = self.claimShopData
vc.hidesBottomBarWhenPushed = true
if var controllers = self.navigationController?.viewControllers, !controllers.isEmpty {
    controllers.removeLast()
    // 重新认证移除导航栏之前能进入重新认证的页面
    if self.revertAuthenticateType != nil, controllers.last is AuthenticationViewController {
        controllers.removeLast()
    }
    controllers.append(vc)
    self.navigationController?.setViewControllers(controllers, animated: true)
}

is 的使用

func removeNoNetworkView() {
    for subView in view.subviews where subView is NetWorkBadView {
        subView.removeFromSuperview()
    }
}