DDD, Error event design.

gistfile1.cs

public abstract class DomainError : IEvent
{
	public override string ToString()
	{
		return Describe();
	}

	protected abstract string Describe();
}

public class OnlineStoreNotFound : DomainError
{
	public OnlineStoreNotFound(OnlineStoreId onlineStoreId)
	{
		OnlineStoreId = Guard.GetNotNull(onlineStoreId, "onlineStoreId");
	}


	public OnlineStoreId OnlineStoreId { get; private set; }

	protected override string Describe()
	{
		return "Online store with identifier '{0}' not found.".FormatString(OnlineStoreId);
	}
}

[Serializable]
public sealed class DomainException<TError> : Exception 
	where TError : DomainError 
{ 
	...

	TError Error { get; private set; }

	...
}


throw new OnlineStoreNotFound(onlineStoreId).AsDomainException();