Objective-C Json 使用

Objective-c json

通过使用NSJSONSerialization 能够Json与Foundation的相互转换。以下详细介绍 Objective-c json 的使用。

Json To Fundation

使用 JSONObjectWithData 能够将 Json 转化为 Foundation。Json的顶层能够是{} 或 []因此能够有 NSDictionary 和 NSArray 两种格式。读取使用 ObjectForKey 返回相应的对象。

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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 能够将 Fundation 转换为 Json。当中 options:NSJSONWritingPrettyPrinted 是分行输出json ,无空格输出使用 option:kNilOptions。

以下这段代码是IOS内购获取商品列表。获取后。将内容加入到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