public void UpdateSpeaker(SpeakerDto speaker)
 {
     using (var db = new ConferenceDudeContext())
     {
         db.Entry(new Speaker { Id = speaker.Id, Name = speaker.FirstName + " " + speaker.LastName }).State =
             EntityState.Modified;
         db.SaveChanges();
     }
 }
 public void DeleteSpeaker(int id)
 {
     using (var db = new ConferenceDudeContext())
     {
         db.Entry(new Speaker { Id = id }).State =
             EntityState.Deleted;
         db.SaveChanges();
     }
 }