Usually, the subscription logic is only a fraction of what a Subject stored more comprehensively (categorized by event type, etc.).Ĭonsole.WriteLine('Subject: Attached an observer.') Ĭonsole.WriteLine('Subject: Detached an observer.') Ĭonsole.WriteLine('Subject: Notifying observers.') In real life, the list of subscribers can be subscribers, is stored in this variable.
For the sake of simplicity, the Subject's state, essential to all The Subject owns some important state and notifies observers when the Program.cs: Conceptual example using System This example illustrates the structure of the Observer design pattern. Identification: The pattern can be recognized by subscription methods, that store objects in a list and by calls to the update method issued to objects in that list. It provides a way to react to events happening in other objects without coupling to their classes. Usage examples: The Observer pattern is pretty common in C# code, especially in the GUI components.
