#380 – Handling Events that Use the EventHandler Delegate Type

Events that return no event data should normally use the built-in EventHandler delegate type.

        public event EventHandler Barked;

EventHandler is a delegate that takes two parameters.

public delegate void EventHandler(object o, EventArgs e);

The first parameter is assumed to be a reference to the object that raised the event.  The second parameter will contain a reference to some subclass of the EventArgs class, if the event does return data, or will be a null value, if the event does not pass data back.

Here’s an example of subscribing to the Barked event defined above.

            // Subscribing to the event
            Dog kirby = new Dog("Kirby");
            kirby.Barked += kirby_Barked;

            kirby.Bark();

And an example of a handler for the Barked event.

        static void kirby_Barked(object o, EventArgs e)
        {
            Console.WriteLine("Kirby barked");
        }
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About Sean
Software developer in the Twin Cities area, passionate about .NET technologies. Equally passionate about my own personal projects related to family history and preservation of family stories and photos.

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