public TwitterMessageBuilder Append(TwitterDirectMessage status, ContactModel sender, bool isHighlight) { if (status == null) { throw new ArgumentNullException("status"); } if (sender == null) { throw new ArgumentNullException("sender"); } // MessageModel serializer expects UTC values TimeStamp = status.CreatedDate.ToUniversalTime(); AppendSenderPrefix(sender, isHighlight); AppendMessage(status.Text); return this; }