Question

I am developing an application for both Android and iPhone and I am having a problem marshalling and unmarshalling on iPhone. With Android it is easy enough, I am using Jackson JSON parser and there are plenty of tutorials online which made it easy to use.

On the iPhone I am using SBJSON parser, however there seems to be a real lack of information online about how to use it effectively.

Take the following piece of JSON

{
"data":{
    "name":[
            {
            "fName":"John",
            "lName":"Doe"
            },
            {
            "fName":"Jane",
            "lName":"Doe"
            }
            ]
}
}

If I were using Java and using Jackson JSON parser, this would be easy. I would set up a Class like

public class Parse {

private Data data;

//get set data class

Then in the data class

public class Data {

private List<Name> name;

//get set name list

then in the name class

public class Name {

private String fName;
private String lName;

//get setters here

That way I have the data split up into a set of objects so I can retrieve the data I need, I can update the JSON if required from Java, then write it out again into a new JSON file, nice and simple, i.e

ObjectMapper mapper = new ObjectMapper();

    Parse test = mapper.readValue(new File("/Users/adam/Documents/JSON/list.json"),
            Parse.class);

    System.out.println(test.getData().getName().get(0).getfName());

or I could set it doing

test.getData().getName().get(0).setfName("test");

What I want to know, is how do I do this with Xcode using SBJSON. I know how to do parse the data, and print it out, but I want to be able to print it out into a set of objects, make a change, then write it out again as I can with Jackson JSON parser. What I have done is

  NSString *file = [[NSBundle mainBundle] pathForResource:@"data" ofType:@"json"];  
 NSData *Data = [NSData dataWithContentsOfFile:file];  
 NSString *jsonString = [[NSString alloc] initWithData:Data encoding:NSUTF8StringEncoding];


 NSDictionary *dictionary = [jsonString JSONValue];

NSArray *name = [dictionary valueForKeyPath:@"data.name"];

NSLog(@"%@", name);

This will get the array of names, but I want to be able to access the first name and last name of each objects, and then update it if I require. Then Write it out again.

Would anyone be able to point me in the right direction. Is it possible to do the same sort of thing I did with Jackson JSON with SBJSON?

Answer 1

Found out how to do it.

Make a class Called List

@interface List : NSObject{
  NSString *fName;
  NSString *lName;
}

@property (nonatomic, retain) NSString *fName;
@property (nonatomic, retain) NSString *lName;

@end

Then implementation synthesise

@synthesize fName, lName;

Then code to create object of List and loop through it

NSMutableArray *array = [[NSMutableArray alloc] init];
List * list;
NSArray * listArray = [MainJSON valueForKeyPath:@"data.name"];

for(NSDictionary * listInfo in listArray) {
    list = [[List alloc] init];
    [list setFName:[listInfo objectForKey:@"fName"]];
    [list setLName:[listInfo objectForKey:@"lName"]];
    [array addObject:list];
}

for (int i = 0; i < [array count]; i++) {
    List* l = [array objectAtIndex: i];
    NSLog(@"%@", [l fName]);
    NSLog(@"%@", [l lName]);
}

Hope this helps anyone else who was trying to do the same thing I was.