static void Main(string[] args)
{
var video = new Video()
{
Id = 1,
Title = "New Video"
};
var videoEncoder = new VideoEncoder(); // instance of the publisher
var mailService = new MailService(); // instance of the subscriber
var messageService = new MessageService(); // instance of the subscriber
// register the subscriber to the event
videoEncoder.VideoEncoded += mailService.OnVideoEncoded;
videoEncoder.VideoEncoded += messageService.OnVideoEncoded;
videoEncoder.Encoder(video);
Console.ReadLine();
}