How to JSON.stringify a dictionary in Swift

Sometimes while working in Swift you may need to serialize (or stringify for those JavaScript minded among us) for transporting that dictionary. To do this you will use Swift's

JSONSerialization

class. The

.data(withJSONObject:options:)

is the method that will help you out with this.

You'll probably want to define a helper function to do this JSON serialization for you. Your helper function could look something like this.

// pass this function a dictionary and you will recieve a string in return
func serializeDictionaryToJSON(dictionary: [String : Any]) -> String {
  do {
    // note here that the `options` argument is itself, optional
    let data = try JSONSerialization.data(
      withJSONObject: dictionary,
      options: .prettyPrinted
    )
    return String(data: data, encoding: String.Encoding.utf8) ?? ""
  } catch {
    // in case anything goes wrong, at the very least return a string
    return ""
  }
}

While serializing dictionaries to stringified JSON in Swift isn't terribly straight forward, you can easily abstract away some of that complexity by adding it to a reusable function like this.