Illustrated C# 2012

C H A P T E R  14

Events

• Publishers and Subscribers
• Overview of Source Code Components
• Declaring an Event
• Subscribing to an Event
• Raising an Event
• Standard Event Usage
• Event Accessors

Publishers and Subscribers

One common requirement in many programs is that when a particular program event occurs, other parts of the program need to be notified that the event has occurred.

One pattern for satisfying this requirement is called the publisher/subscriber pattern. In this pattern, a class, called the publisher, defines a set of events that other parts of the program might be interested in. Other classes can then “sign up” to be notified by the publisher when these events occur. These subscriber classes “sign up” for notification by supplying ...