AggregateRoot.cs

public abstract class AggregateRoot{
  private readonly List<INotification> _domainEvents = new List<INotification>();
  public IReadOnlyCollection<INotification> DomainEvents => _domainEvents.AsReadOnly();

  public void AddDomainEvent(INotification eventItem)
  {
      _domainEvents.Add(eventItem);
  }

  public void RemoveDomainEvent(INotification eventItem)
  {
      _domainEvents.Remove(eventItem);
  }

  public void ClearDomainEvents()
  {
      _domainEvents.Clear();
  }
}