Ios 如何从密钥为x的NSDictionary创建新的NSDictionary

我有一个应用程序，通过web api从mysql服务器获取一些json数据，如下所示：

[[API sharedInstance] commandWithParams:[NSMutableDictionary dictionaryWithObjectsAndKeys:@"streamGames", @"command", nil] onCompletion:^(NSDictionary *json) {

    //got stream

     [[API sharedInstance] setGames:[json objectForKey:@"result"]];

这给了我：

{
    awayScor = 3;
    data = "2014-04-11";
    gameType = 1;
    homeScor = 2;
    homeTeam = "Herning Blue Fox";
    time = "21:00";
},
    {
    awayScor = 1;
    data = "2014-04-08";
    gameType = 2;
    homeScor = 2;
    homeTeam = "SønderjyskE";
    time = "19:00";
},

---

现在，我想做的是制作一个新的NSDictionary，其中我只添加数据，比如gameType=1，这样我就有了一个新的NSDictionary，用于蚀刻gameType。

如果我正确理解了这个问题

NSArray *games; // Get this from somewhere
NSMutableDictionary *gameTypes = [NSMutableDictionary dictionary];

for (NSDictionary *game in games) {
    NSNumber *gameType = game[@"gameType"];
    NSMutableArray *gamesForType = gameTypes[gameType];
    if (!gamesForType) {
        gamesForType = [NSMutableArray array];
        gameTypes[gameType] = gamesForType;
    }
    [gamesForType addObject:game];
}

现在，

gameTypes

将是一个游戏类型字典，用于该类型的数组游戏