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Events

Events. Traditional Console applications operate by waiting for a user to press a key or type a command and press the  Enter  key. Then they perform some pre-defined operation and either quit or return to the original prompt that they started from.

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Events

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  1. Events

  2. Traditional Console applications operate by waiting for a user to press a key or type a command and press the Enter key. Then they perform some pre-defined operation and either quit or return to the original prompt that they started from

  3. This works, but is inflexible in that everything is hard-wired and follows a rigid path of execution. • In contrast, modern GUI programs operate on an event-based model. • That is, some event in the system occurs and interested modules are notified so they can react appropriately. 

  4. With Windows Forms, there is not a polling mechanism taking up resources and you don't have to code a loop that sits waiting for input. It is all built into the system with events.

  5. A C# event is a class member that is activated whenever the event it was designed for occurs. •  I like to use the term "fires" when the event is activated. • Anyone interested in the event can register and be notified as soon as the event fires. • At the time an event fires, registered methods will be invoked.

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