How to convert an NSDictionary to a JSON object?

Question

I'm still learning JSON, and using SBJSON. How would I go about taking an NSDictionary and converting it into a JSON object similar to this:

{"id":"123","list":"456","done":1,"done_date":1305016383}

Answer 1

Use the category that SBJSON adds to NSDictionary:

NSString *jsonString = [dictionary JSONRepresentation];

Just name the keys and values appropriately in the dictionary and SBJSON will do the work for you

Answer 2

There is a JSON-API (since iOS5 and OS X 10.7) in the official iOS-SDK it's called:

+ (NSData *)dataWithJSONObject:(id)obj
                       options:(NSJSONWritingOptions)opt
                         error:(NSError **)error

See Guillaume's post for more information how to use it: https://stackoverflow.com/a/9020923/261588

Works like a charm.

Answer 3

For those that are using JSONKit instead of SBJSON:

JSONKit also provides a category for NSDictionary

NSString *jsonString = [dictionary JSONStringWithOptions:JKSerializeOptionNone error:nil]