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 or 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

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]; } 

Answer 1

 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。

Answer 2

t是nil，你必须分配/初始化它：

 TickerData *t = [[TickerData alloc] init]; 

Answer 3

尝试一下….

 NSURL *url = [NSURL URLWithString:@"https://blockchain.info/ticker"]; NSLog(@"API : %@",url); NSMutableData *jsonData = [NSMutableData dataWithContentsOfURL:url]; NSString *data = [[NSString alloc] initWithBytes: [jsonData mutableBytes] length:[jsonData length] encoding:NSUTF8StringEncoding]; dictionary = [data JSONValue]; NSDictionary *dict = [dictionary objectForKey:@"AUD"]; NSLog(@"%@",dict); NSString *last = [dict valueForKey:@"last"]; NSLog(@"%@",last);