NSMutableArray *marr = [[NSMutableArray alloc]initWithArray:self.navigationController.viewControllers];
    for (UIViewController *vc in marr) {
        if (vc == self) {
            [marr removeObject:vc];
            break;          //break一定要加，不加有时候有bug
        }
    }
    self.navigationController.viewControllers = marr;

从当前界面进入下下级界面

 CreateQuNotiVController *vc1 = [[CreateQuNotiVController alloc] initQucikWithType:(TYCyclePagerCellTypeSMS) cache:NO];
            vc1.hidesBottomBarWhenPushed = YES;
            
            UIViewController *vc2 = [[NSClassFromString(@"GreetingCardViewController") alloc] init];
            vc2.hidesBottomBarWhenPushed = YES;
            
            [self.navigationController setViewControllers:@[self, vc2] animated:YES];