Check out example codes for "stringify json swift". It will help you in understanding the concepts better.

Code Example 1

do {
        let arrJson = try JSONSerialization.data(withJSONObject: dataAddress, options: JSONSerialization.WritingOptions.prettyPrinted)
        let string = String(data: arrJson, encoding: String.Encoding(rawValue: String.Encoding.utf8.rawValue))
        let tempJson = string! as String
        print("%%%%%%",tempJson)
    }catch let error as NSError{
        print(error.description)
    }

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