ios – 使用字典解析JSON数组

我在 JSON文件中找到我想要的数据时遇到了一些麻烦.这是我的控制台输出的缩短版本：

{
    AUD =     {
        15m = "125.15547";
        24h = "124.74";
        buy = "121.0177";
        last = "125.15547";
        sell = "123.44883";
        symbol = "$";
    };
    BRL =     {
        15m = "120.34";
        24h = "120.34";
        buy = "120.34";
        last = "120.34";
        sell = "120.34";
        symbol = "R$";
    };
    CAD =     {
        15m = "129.08612";
        24h = "131.07";
        buy = "128.66227";
        last = "129.08612";
        sell = "129.08612";
        symbol = "$";
    };
}

我正在尝试使用内置的JSON解析库来解析文件.这是我的viewDidLoad方法中的解析器：

_tickerArray = [NSMutableArray array];

    NSURL *tickerDataURL = [NSURL URLWithString:@"https://blockchain.info/ticker"];
    NSData *jsonData = [NSData dataWithContentsOfURL:tickerDataURL];
    NSError *error = nil;
NSDictionary *dataDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];
    NSLog(@"%@",dataDictionary);
    NSArray *ar = [NSArray arrayWithObject:dataDictionary];
    for (NSString *key in [dataDictionary allKeys]) {
        for (NSDictionary *dict in ar) {
            TickerData *t;
            t.currency = [dict objectForKey:key];
            t.symbol = [dict objectForKey:@"symbol"];
            t.last = [dict objectForKey:@"last"];
            [_tickerArray addObject:t];
        }

    }

我想将货币代码(如AUD或BRL)与货币字典中包含的一些其他数据一起存储到t.currency中,但现在我的应用程序崩溃了.
错误代码：

NSInvalidArgumentException',reason: '*** -[__NSArrayM insertObject:atIndex:]: object cannot be nil

似乎没有任何对象被添加到_tickerArray中

帮帮我？

编辑：使用填充其他字段的正确数据显示键：

NSDictionary *dataDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];
    NSLog(@"%@",dataDictionary);


    for (NSString *key in [dataDictionary allKeys]) {
        NSDictionary *dic=[dataDictionary objectForKey:key];
            TickerData *t=[[TickerData alloc] init];
            t.currency = key;//EDITED
            t.symbol = [dic objectForKey:@"symbol"];
            t.last = [dic objectForKey:@"last"];
            [_tickerArray addObject:t];

    }

解决方法

NSDictionary *dataDictionary = [NSJSONSerialization JSONObjectWithData:jsonData options:0 error:&error];
NSLog(@"%@",dataDictionary);
//NSArray *ar = [NSArray arrayWithObject:dataDictionary];//REMOVED
for (NSString *key in [dataDictionary allKeys]) {
    NSDictionary *dic=[dataDictionary objectForKey:key];//ADDED
    for (NSString *dickey in [dic allKeys]) { //MODIFIED
        NSDictionary *dict=[dic objectForKey:dicKey];//ADDED
        TickerData *t=[[TickerData alloc] init];//ALLOC INIT ?
        t.currency = key;//EDITED
        t.symbol = [dict objectForKey:@"symbol"];
        t.last = [dict objectForKey:@"last"];
        [_tickerArray addObject:t];
    }

}

您的数据不包含任何数组,其所有词典,请尝试上面的代码,请参阅注释..

希望它有效..

编辑：

是的,您也初始化了对象,如上面其他答案所示.