KVO 集合数组观察

集合数组观察

• [[self.person mutableArrayValueForKey:@"dateArray"] addObject:@"hello"]
• 通过[self.person.dateArray addObject:@"hello”];获取不到
• KVC

    self.person.dateArray = [NSMutableArray arrayWithCapacity:1];
//    [self.person.dateArray addObject:@"hello"];//无法观察到
    [[self.person mutableArrayValueForKey:@"dateArray"] addObject:@"hello"];//正确的