判断视图控制器里的viewcontrollers和判断某个对象是

判断视图控制器里的viewcontrollers

NSArray *viewControllers = self.navigationController.viewControllers;
for (UIViewController *vc in viewControllers) {
    if ([vc isMemberOfClass:[LevelUpViewController class]]) {
        [self.navigationController popToViewController:vc animated:YES];
    }
}

判断某个对象是否在一个数组中
-(BOOL)containsObject:(id)anObject;