Save RTF from UITextView using NSFileWrapper on Xamarin.iOS

SaveRTFFromUITextView.cs

NSError error1 = null;
NSError error2 = null;

var atts = new NSAttributedStringDocumentAttributes ();
atts.DocumentType = NSDocumentType.RTF;

using (var wrapper = textView.AttributedText.GetFileWrapperFromRange (new NSRange (0, textView.Text.Length), atts, ref error1))
{
  wrapper.Write (new NSUrl ("...Edited.rtf", false), NSFileWrapperWritingOptions.Atomic, new NSUrl ("...Sample.rtf", false), out error2);
}