Objective-C Json 使用

Objective-c json

通过使用NSJSONSerialization 可以Json与Foundation的相互转换。下面具体介绍 Objective-c json 的使用。

Json To Fundation

使用 JSONObjectWithData 可以将 Json 转化为 Foundation。Json的顶层可以是{} 或 []因此可以有 NSDictionary 和 NSArray 两种格式。读取使用 ObjectForKey 返回对应的对象。

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NSString* items = @ "{" items ":[" item0 "," item1 "," item2 "]}" ;   NSData * data = [ items dataUsingEncoding : NSUTF8StringEncoding ] ;   NSError * error = nil ;   id jsonObject = [ NSJSONSerialization JSONObjectWithData : data                      options : NSJSONReadingAllowFragments                      error : & amp ; error ] ;   if ( [ jsonObject isKindOfClass : [ NSDictionary class ] ] ) {        NSDictionary * dictionary = ( NSDictionary * ) jsonObject ;        NSLog ( @ "Dersialized JSON Dictionary = %@" , dictionary ) ;   } else if ( [ jsonObject isKindOfClass : [ NSArray class ] ] ) {        NSArray * nsArray = ( NSArray * ) jsonObject ;        NSLog ( @ "Dersialized JSON Array = %@" , nsArray ) ;   } else {        NSLog ( @ "An error happened while deserializing the JSON data." ) ;   }   NSDictionary * dict = ( NSDictionary * ) jsonObject ;   NSArray* arr = [ dict objectForKey : @ "items" ] ; NSLog ( @ "list is %@" , arr ) ;

Fundation To Json

使用 dataWithJsonObject 可以将 Fundation 转换为 Json。其中 options:NSJSONWritingPrettyPrinted 是分行输出json ,无空格输出使用 option:kNilOptions。

下面这段代码是IOS内购获取商品列表。获取后，将内容添加到Json中。

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NSArray * myProduct = response . products ; NSDictionary * myDict ; NSMutableDictionary * dict = [ NSMutableDictionary                                  dictionaryWithCapacity : 4 ] ;   for ( int i    = 0 ; i & lt ; myProduct . count ; ++ i ) {        //NSLog(@"----------------------");      //NSLog(@"Product title: %@" ,[myProduct[i] localizedTitle]);      //NSLog(@"Product description: %@" ,[myProduct[i] localizedDescription]);      //NSLog(@"Product price: %@" ,[myProduct[i] price]);      //NSLog(@"Product id: %@" ,[myProduct[i] productIdentifier]);        myDict = [ NSDictionary dictionaryWithObjectsAndKeys :                      [ myProduct [ i ] localizedTitle ] , @ "title" ,                      [ myProduct [ i ] localizedDescription ] , @ "desc" ,                      [ myProduct [ i ] price ] , @ "price" ,                      [ myProduct [ i ] productIdentifier ] , @ "product" , nil ] ;        [ dict setValue : myDict forKey : [ myProduct [ i ] productIdentifier ] ] ; } if ( [ NSJSONSerialization isValidJSONObject : dict ] ) {      NSError* error ;      NSData * str = [ NSJSONSerialization dataWithJSONObject : dict                          options : kNilOptions error : & amp ; error ] ;      NSLog ( @ "Result: %@" , [ [ NSString alloc ] initWithData : str                              encoding : NSUTF8StringEncoding ] ) ; } else {      NSLog ( @ "An error happened while serializing the JSON data." ) ; }

本篇博客出自阿修罗道，转载请注明出处，禁止用于商业用途：http://blog.csdn.net/fansongy/article/details/40919425