We often come across a condition where JSON string is to be sent to server. for example parameters like username & password is to be posted as JSON String for validating credentials from server.

Best practice is to create an extension of NSDictionary and add a function with a name of your choice(func jsonString here for now) that will return JSONString as String.

for Swift 2.x

func jsonString()->String?{

    do{

      let jsonData:NSData = try NSJSONSerialization.dataWithJSONObject(self, options: NSJSONWritingOptions.PrettyPrinted)

      let jsonString = String(data: jsonData, encoding: NSUTF8StringEncoding)

      return jsonString

    }

    catch{

      return nil

    }

  }

for Swift 3.0

func jsonString()->String?{

    do{

      let jsonData:NSData = try JSONSerialization.data(withJSONObject: self, options: JSONSerialization.WritingOptions.prettyPrinted) as NSData

      let jsonString = String(data: jsonData as Data, encoding: String.Encoding.utf8)

      return jsonString

    }

    catch{

      return nil

    }

  }