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Deligates

Delegates

A delegate is a type that represents references to methods with a particular parameter list and return type.When you instantiate a delegate, you can associate its instance with any method with a compatible signature and return type. You can invoke (or call) the method through the delegate instance.

When and Why to use Delegates

A delegate can be seen as a placeholder for a/some method(s).

By defining a delegate, you are saying to the user of your class "Please feel free to put any method that match this signature here and it will be called each time my delegate is called".

Typical use is of course events. All the OnEventX delegate to the methods the user defines.

Delegates are useful to offer to the user of your objects some ability to customize their behaviour. Most of the time, you can use other ways to achieve the same purpose and I do not believe you can ever be forced to create delegates. It is just the easiest way in some situations to get the thing done.

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