【原】NSMutableDictionary与NSMutableArray

    NSMutableDictionary *dic = [NSMutableDictionary dictionary];
    [dic setValue:@"1" forKey:@"a"];
    [dic setValue:@"3" forKey:@"c"];
    [dic setValue:@"2" forKey:@"b"];
    NSLog(@"dic:%@",dic);

 结果是 abc

若换成NSMutableArray，用addObject的方法，结果是插入的顺序。

所以字典与数组有这样的不同