Swift Encode/decode emojis

I'm trying to encode and decode Emojis to send them to my database.

I use this to encode:

var comentario = String()
let data = Comment.data(using: String.Encoding.nonLossyASCII, allowLossyConversion: true)
if let data = data {
    let emojiString = NSString(data: data, encoding: String.Encoding.utf8.rawValue)! as String
    comentario = emojiString
}

And it works. But now I don't know how to decode the emoji.

This is the type of encode ---> \ud83d\ude1a