如何通过字典键过滤字典的数组

这是我的JSON.This总共250个国家，我只列出3下面。 在这里我需要做的事情是我有parsing的国家进入七个不同的arrays基于大陆。

{ "geonames" : [ { "languages" : "ca", "east" : 1.786542777831983, "continent" : "EU", "geonameId" : 3041565, "population" : "84000", "areaInSqKm" : "468.0", "countryName" : "Andorra", "south" : 42.42849259876837, "countryCode" : "AD", "capital" : "Andorra la Vella", "isoAlpha3" : "AND", "fipsCode" : "AN", "isoNumeric" : "020", "west" : 1.407186714111276, "continentName" : "Europe", "north" : 42.65604389629997, "currencyCode" : "EUR" }, { "languages" : "ar-AE,fa,en,hi,ur", "east" : 56.38166046142578, "continent" : "AS", "geonameId" : 290557, "population" : "4975593", "areaInSqKm" : "82880.0", "countryName" : "United Arab Emirates", "south" : 22.63332939147949, "countryCode" : "AE", "capital" : "Abu Dhabi", "isoAlpha3" : "ARE", "fipsCode" : "AE", "isoNumeric" : "784", "west" : 51.58332824707031, "continentName" : "Asia", "north" : 26.08415985107422, "currencyCode" : "AED" }, { "languages" : "fa-AF,ps,uz-AF,tk", "east" : 74.879448, "continent" : "AS", "geonameId" : 1149361, "population" : "29121286", "areaInSqKm" : "647500.0", "countryName" : "Afghanistan", "south" : 29.377472, "countryCode" : "AF", "capital" : "Kabul", "isoAlpha3" : "AFG", "fipsCode" : "AF", "isoNumeric" : "004", "west" : 60.478443, "continentName" : "Asia", "north" : 38.483418, "currencyCode" : "AFN" } ] } 

Answer 1

这是如何过滤你的geonames数组。 filterArrayByADictionary方法获取数组和search条件并返回经过滤的字典数组。

 -(NSArray *)filterArrayByADictionary:(NSArray *)aArray andKey:(NSString *)aPredicte { NSPredicate *filter = [NSPredicate predicateWithFormat:aPredicte]; return [aArray filteredArrayUsingPredicate:filter]; } 

你可以像这样调用这个方法。

 NSArray *AsiaCounties = [self filterArrayByADictionary: geonames andKey:@"continent = 'AS'"]; NSArray *EuropeCounties = [self filterArrayByADictionary: geonames andKey:@"continent = 'EU'"]; // rest of the continents... 

Answer 2

假设你在NSDictionary了这个输出：

 NSDictionary *mainDic; NSMutableArray *arr = [NSMutableArray new]; NSMutableArray *arrcontinent1 = [NSMutableArray new]; NSMutableArray *arrcontinent2 = [NSMutableArray new]; arr = [mainDic valueForKey:@"geonames"]; for(int i=0; i<[arr count];i++){ NSDictionary *dic = [arr objectAtIndex:i]; if([[dic valueForKey:@"continent"] isEqualToString:@"EU"]){ [arrcontinent1 addObject:dic]; } else if([[dic valueForKey:@"continent"] isEqualToString:@"AS"]){ [arrcontinent2 addObject:dic]; } // and so on...... }