如何構建特定格式的JSON字符串？

Question

我想格式化使用NSJSONSerialization以下格式的JSON字符串：

{ 
"data":{"userName":"rrullo","password":"rrullo!"}, 
"meta":{"appId":"S3B9CU4R2B9JTXV9254Y","appVersion":"2.1.0","serverVersion":"1.1.0","platform":"iOS","deviceToken":"1234","tm_session_id":"BB00000"} 
} 

但我不知道如何來實現，雖然這種格式。有人可以幫助我嗎......

Answer 1

首先用你的'meta'和'data'信息填充兩個NSDictionaries。然後添加這些入主的NSDictionary，然後序列化使用NSJsonSerialization

NSDictionary * metaDict = [[NSDictionary alloc] initWithObjectsAndKeys: 
@"appId", @"S3B9CU4R2B9JTXV9254Y", @"appVersion", @"2.1.0", @"serverVersion", @"1.1.0", @"platform", @"iOS",..., nil]; 

NSDictionary * dataDict = [[NSDictionary alloc] initWithObjectsAndKeys: 
@"userName", @"rrullo", @"password", @"rrullo!", nil]; 

NSDictionary * mainDict = [[NSDictionary alloc] initWithObjectsAndKeys: 
@"data", dataDict, @"meta", metaDict, nil]; 

現在你可以使用NSJsonSerialization到mainDict轉換成的NSString

NSError *error; 
NSData *jsonData = [NSJSONSerialization dataWithJSONObject:mainDict 
                options:NSJSONWritingPrettyPrinted 
                error:&error]; 
NSString *jsonString = [[NSString alloc] initWithData:jsonData encoding:NSUTF8StringEncoding]; 

希望這有助於

Answer 2

NSDictionary dictData = @{ @"UserName":@"rrullo", @"password":@"rrullo!"}; 
NSDictionary dictMeta = @{ @"appId":@"S3B9CU4R2B9JTXV9254Y", etc}; 
NSDictionary dictJSON = @{ @"data":dictData, @"meta":dictMeta }; 

NSError *error = nil; 
NSData *dataJSON = [NSJSONSerialization dataWithJSONObject:dictJSON 
                options:NSJSONWritingPrettyPrinted 
                error:&error]; 
if (!error) { 
    NSString *jsonString = [[NSString alloc] initWithData:dataJSON encoding:NSUTF8StringEncoding]; 
} else { 
    NSLog(@"Error: %@", error); 
}