项目经验积累－navigation栈清空

显示登录选择，然后跳转进入注册，注册之后，直接进入浏览界面这一需求

// 清空nav栈

NSMutableArray *array = [[NSMutableArray alloc] initWithArray:self.navigationController.viewControllers]; [array removeAllObjects]; self.navigationController.viewControllers = array;