CODEWITHSUNDEEP
iphoneobjective-cjson
Radu
Radu

Reputation: 3494

Convert an object into Json using SBJson or other JSON library

I need a easy to use library whit examples for converting NSObjects to JSON and back again, I found a ton of parseing examples on the net for parsing JSon but not too much on converting NSObject to JSON using SBJSON, Anybody body have a good tutorial or a sample code to convert NSObject to JSON ?

Upvotes: 2

Views: 10596

Answers (3)

suresh
suresh

Reputation: 2395

From JSON String to Objects:

SBJsonParser *parser = [[SBJsonParser alloc] init];

// gives array as output

id objectArray = [parser objectWithString:@"[1,2,3]"]; 

// gives dictionary as output

id objectDictionary = [parser objectWithString:@"{\"name\":\"xyz\",\"email\":\"[email protected]\"}"];

From Objects to JSON String:

SBJsonWriter *writer = [[SBJsonWriter alloc] init];

id *objectArray = [NSArray arrayWithObjects:@"Hello",@"World", nil];

// Pass an Array or Dictionary object.

id *jsonString = [writer stringWithObject:objectArray];

Upvotes: 2

karim
karim

Reputation: 15589

Using SBJson, to convert a object to JSON string, you have to override the proxyForJson method. Like the following,

The .h file,

@interface MyCustomObject : NSObject {
    NSString *receiverFirstName;
    NSString *receiverMiddleInitial;
    NSString *receiverLastName;
    NSString *receiverLastName2;
}
@property (nonatomic, retain) NSString *receiverFirstName;
@property (nonatomic, retain) NSString *receiverMiddleInitial;
@property (nonatomic, retain) NSString *receiverLastName;
@property (nonatomic, retain) NSString *receiverLastName2;

- (id) proxyForJson;
- (int) parseResponse :(NSDictionary *) receivedObjects;
}

In the implementation file,

    - (id) proxyForJson {

        return [NSDictionary dictionaryWithObjectsAndKeys:
            receiverFirstName, @"ReceiverFirstName",
            receiverMiddleInitial, @"ReceiverMiddleInitial",
            receiverLastName, @"ReceiverLastName",
            receiverLastName2, @"ReceiverLastName2",
            nil ];
    }

And to get the object from the JSON string you have to write a parseResponse method like this,

- (int) parseResponse :(NSDictionary *) receivedObjects {
    self.receiverFirstName = (NSString *) [receivedObjects objectForKey:@"ReceiverFirstName"];
    self.receiverLastName = (NSString *) [receivedObjects objectForKey:@"ReceiverLastName"];

    /* middleInitial and lastname2 are not required field. So server may return null value which
     eventually JSON parser return NSNull. Which is unrecognizable by most of the UI and functions.
     So, convert it to empty string. */ 
    NSString *middleName = (NSString *) [receivedObjects objectForKey:@"ReceiverMiddleInitial"];
    if ((NSNull *) middleName == [NSNull null]) {
        self.receiverMiddleInitial = @"";
    } else {
        self.receiverMiddleInitial = middleName;
    }

    NSString *lastName2 = (NSString *) [receivedObjects objectForKey:@"ReceiverLastName2"];
    if ((NSNull *) lastName2 == [NSNull null]) {
        self.receiverLastName2 = @"";
    } else {
        self.receiverLastName2 = lastName2;
    }

    return 0;
}

Upvotes: 12

Patrick Perini
Patrick Perini

Reputation: 22633

With SBJSON, it's really simple.

NSString *myDictInJSON = [myDict JSONRepresentation];
NSString *myArrayInJSON = [myArray JSONRepresentation];

Of course, to go the other way array, do:

NSDictionary *myDict = [myDictInJSON JSONValue];
NSArray *myArray = [myArrayInJSON JSONValue];

Upvotes: 13

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