A simple code to demonstrate how events work on C#. this is based on a great video by Mosh Hamedanian: https://www.youtube.com/watch?v=jQgwEsJISy0

events

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace @event
{
    class Program
    {
        static void Main(string[] args)
        {
            Video video = new Video { Title = "my video" };
            VideoEncoder videoEncoder = new VideoEncoder();
            EmailService emailService = new EmailService();
            SmsService smsService = new SmsService();

            videoEncoder.VideoEncoded += emailService.OnVideoEncoded;
            videoEncoder.VideoEncoded += smsService.OnVideoEncoded;

            videoEncoder.Encode(video);
        }
    }


    public class Video
    {
        public string Title { get; set; }
    }

    public class VideoEventArgs : EventArgs
    {
        public Video Video { get; set; }
    }

    public class VideoEncoder
    {
        public event EventHandler<VideoEventArgs> VideoEncoded;
        public void Encode(Video video)
        {
            Console.WriteLine("Encoding...");
            OnVideoEncoded(video);
        }

        protected virtual void OnVideoEncoded(Video video)
        {
            if (VideoEncoded != null)
                VideoEncoded(this, new VideoEventArgs() { Video = video });
        }
    }

    public class EmailService
    {
        public void OnVideoEncoded(object source, VideoEventArgs e)
        {
            Console.WriteLine("Sending Email..." + e.Video.Title);
        }

    }

    public class SmsService
    {
        public void OnVideoEncoded(object source, VideoEventArgs e)
        {
            Console.WriteLine("Sending Text Message..." + e.Video.Title);
        }
    }
}