如何将JSON数据格式化为Objective-C变量？

Question

在我的iOS应用中，我正在获取一些通知数据。此数据格式如下：

{ 
"data": [ 
    { 
     "to": "1", 
     "from": "0", 
     "text": "Person X liked photo Y.", 
     "read": "1", 
     "date": "1 month ago" 
    }, 
    { 
     "to": "1", 
     "from": "0", 
     "text": "Person X liked status Y.", 
     "read": "1", 
     "date": "1 month ago" 
    }, 
    { 
     "to": "1", 
     "from": "0", 
     "text": "Person X wants to be your friend.", 
     "read": "1", 
     "date": "1 month ago" 
    }, 
    { 
     "to": "1", 
     "from": "0", 
     "text": "Person X is a bit of a stalker.", 
     "read": "1", 
     "date": "1 month ago" 
    }, 
] 
} 

我知道如何与在data元素只有一个变量JSON格式数据，但是这一次得到了与内容的数组。我需要在下面的代码中更改什么？

NSLog(@"connectionDidFinishLoading"); 
NSLog(@"Succeeded! Received %d bytes of data",[self.notificationData length]); 

// convert to JSON 
NSError *notificationError = nil; 
NSDictionary *notificationRes = [NSJSONSerialization JSONObjectWithData:self.notificationData options:NSJSONReadingMutableLeaves error:&myError]; 

NSLog(@"%@", notificationRes); 

// extract specific value... 
NSDictionary *notificationSwitchValues = [notificationRes objectForKey:@"data"]; 

NSLog(@"%@", notificationSwitchValues); 

NSString *text = [notificationSwitchValues objectForKey:@"text"]; 

NSLog(@"%@", text); 

Answer 1

[notificationRes objectForKey:@"data"]是数组，因此必须

NSArray *notificationSwitchValues = notificationRes[@"data"]; 
NSLog(@"%@", notificationSwitchValues); 
for (NSDictionary *notificationSwitchValue in notificationSwitchValues) { 
    NSString *text = notificationSwitchValue[@"text"]; 
} 

Answer 2

NSDictionary *notificationSwitchValues = [notificationRes objectForKey:@"data"]; 

上述代码应更换到

NSArray *notificationSwitchValues = [notificationRes objectForKey:@"data"]; 

然后从阵列存取元件，这将是再次从最后一个字典访问dictionary.Then元素。

Answer 3

NSMutableArray *entitys = [NSMutableArray new]; 
for (NSDictionary *dictionary in notificationRes) { 
    StrangeJSONData *strangeJSONData = [StrangeJSONData strangeJSONDataFromDictionary:dictionary]; 
    [entitys addObject:strangeJSONData]; 
} 

@interface StrangeJSONData : NSObject 
@property (nonatomic, strong) NSNumber *to; 
@property (nonatomic, strong) NSNumber *from; 
@property (nonatomic, strong) NSNumber *read; 
@property (nonatomic, strong) NSString *date; 
@property (nonatomic, strong) NSString *text; 
+ (instancetype)strangeJSONDataFromDictionary:(NSDictionary *)dictionary; 
@end 

@implementation StrangeJSONData 

+ (instancetype)strangeJSONDataFromDictionary:(NSDictionary *)dictionary { 
    StrangeJSONData *strangeJSONData = [[StrangeJSONData alloc] init]; 
    strangeJSONData.to = dictionary[@"to"]; 
    strangeJSONData.from = dictionary[@"from"]; 
    strangeJSONData.read = dictionary[@"read"]; 
    strangeJSONData.date = dictionary[@"date"]; 
    strangeJSONData.date = dictionary[@"text"]; 
    return strangeJSONData; 
} 

@end 

Answer 4

我强烈推荐一些第三方开放源代码库，可以为你做，并提供许多其他功能。

尝试其中之一：

• 护肩：https://github.com/Mantle/Mantle
• JSONModel：http://www.jsonmodel.com