oc 不可变字典NSDictionary中的键值对的修改

 NSArray *tempArray = @[@{
                                   @"distanceWord":@"不限",
                                   @"distanceName":@"",
                                   @"select":@(1),
    },@{
                                   @"distanceWord":@"1km",
                                   @"distanceName":@"1000",
                                   @"select":@(0),
},@{
                                   @"distanceWord":@"3km",
                                   @"distanceName":@"3000",
                                   @"select":@(0),
    },@{
                                   @"distanceWord":@"5km",
                                   @"distanceName":@"5000",
                                  @"select":@(0),
    },@{
                                   @"distanceWord":@"10km",
                                   @"distanceName":@"10000",
                                  @"select":@(0),
    }];
// 将不可变数组放在创建的可变数组中
  NSMutableArray *distanceDataArray = [[NSMutableArray alloc]initWithArray:tempArray];
// 获取数组中的下标为2对应的字典
 NSDictionary *dic = self.distanceDataArray[2];// NSDictionary *item = [self.distanceDataArray objectAtIndex:2];
// 将不可变字典放在创建的可变字典中
NSMutableDictionary *mutDic = [NSMutableDictionary dictionaryWithDictionary:dic];
// 修改select对应的值
 [mutableItem setObject:@(1) forKey:@"select"];
// 更新distanceDataArray中下标为2的字典
[self.distanceDataArray setObject:mutDic atIndexedSubscript:2];