using ConsoleApp1.intf; namespace ConsoleApp1.pubsub { public abstract class MsgSubscriber : ISubscriber { public void FireEvent(IMessage message) { if (message == null) { return; } if (String.IsNullOrEmpty(message.Text)) { return; } string sMsg = $"{DateTime.Now:D} {message.ToString()}"; message.Text = sMsg; ObjFire(message); } protected abstract void ObjFire(IMessage sMsg); } }