Custom event not raising in EventHandler .NET CORE - .net-core

Question

Using .net core I'm implementing class library to push bulk emails into Email server.Email server will consume my email list and gives feedback after complete.this will take 20-30 seconds.When I got feedback from email server I need to fire method.
I have referred this article to implement event handler.But when I debug it
EventHandler OnFeedbackReceived
parameter is null.see image below
This is class library code.
using System;
using System.Text;
using Newtonsoft.Json;
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using System.Collections.Generic;
namespace OSH_EmailServerLibrary
{
public static class EmailMQServerLibrary
{
public static event EventHandler<EmailFeedbackEventArgs> OnFeedbackReceived;
public static void PushToMQ(List<EmailMessage> _emailList)
{
//
// Long RabbitMQ msg push code here
//
EmailMessageFeedback feedback = new EmailMessageFeedback { Description = "Completed", SuccessCount = 10, FailedCount = 0 };
SendFeedback(feedback);
Console.ReadLine();
}
private static EmailMessageFeedback SendFeedback(EmailMessageFeedback feedback)
{
if (OnFeedbackReceived != null)
{
OnFeedbackReceived(feedback, new
EmailFeedbackEventArgs(feedback));
}
return feedback;
}
}
public class EmailFeedbackEventArgs : EventArgs
{
public EmailFeedbackEventArgs(EmailMessageFeedback _feedback)
{
feedback = _feedback;
}
public EmailMessageFeedback feedback { get; set; }
}
}
This is how I user it in a console application
using System;
using System.Collections.Generic;
using System.Text;
using Newtonsoft.Json;
using OSH_EmailServerLibrary;
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
namespace EmailServerSenderSampleConsole
{
class Program
{
static void Main(string[] args)
{
List<EmailMessage> _emailList = _emails.GetAllEmailToSend();
EmailMQServerLibrary.PushToMQ(_emailList);
EmailMQServerLibrary.OnFeedbackReceived += EmailMQServerLibrary_OnFeedbackReceived;
}
private static void EmailMQServerLibrary_OnFeedbackReceived(object sender, EmailFeedbackEventArgs e)
{
}
}
}

Answer 1

Finally Fixed my issue.Issue was not in my class library.Issue was I did subscribe event after PushToMQ() in my console application which is wrong..Thank you so much #Hans Passant helping me out.
here is my corrected answer.I think this will help others like me.
Class Library >>
using System;
using System.Text;
using Newtonsoft.Json;
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
using System.Collections.Generic;
namespace OSH_EmailServerLibrary
{
public static class EmailMQServerLibrary
{
public static event EventHandler<EmailFeedbackEventArgs> OnFeedbackReceived;
public static void PushToMQ(List<EmailMessage> _emailList)
{
//
// Long RabbitMQ msg push code here
//
EmailMessageFeedback feedback = new EmailMessageFeedback { Description = "Completed", SuccessCount = 10, FailedCount = 0 };
SendFeedback(feedback);
Console.ReadLine();
}
private static EmailMessageFeedback SendFeedback(EmailMessageFeedback feedback)
{
if (OnFeedbackReceived != null)
{
OnFeedbackReceived(feedback, new
EmailFeedbackEventArgs(feedback));
}
return feedback;
}
}
public class EmailFeedbackEventArgs : EventArgs
{
public EmailFeedbackEventArgs(EmailMessageFeedback _feedback)
{
feedback = _feedback;
}
public EmailMessageFeedback feedback { get; set; }
}
}
Console Application >>
using System;
using System.Collections.Generic;
using System.Text;
using Newtonsoft.Json;
using OSH_EmailServerLibrary;
using RabbitMQ.Client;
using RabbitMQ.Client.Events;
namespace EmailServerSenderSampleConsole
{
class Program
{
static void Main(string[] args)
{
List<EmailMessage> _emailList = _emails.GetAllEmailToSend();
EmailMQServerLibrary.OnFeedbackReceived +=
EmailMQServerLibrary_OnFeedbackReceived; //-- worked
EmailMQServerLibrary.PushToMQ(_emailList);
//EmailMQServerLibrary.OnFeedbackReceived +=
EmailMQServerLibrary_OnFeedbackReceived; -- Not working like this
}
private static void EmailMQServerLibrary_OnFeedbackReceived(object sender, EmailFeedbackEventArgs e)
{
}
}
}