How to name methods that are registered to events

Question

Hello,

assume i have class that exposes the following event

public event EventHandler Closing

How to name methods that are registered to this event. Do you prefer to name the methods like they are generated by Visual Studio (aka. +=, Tab, Tab)

private void TheClass_Closing( object sender, EventArgs e )

or do you use your own style to name these methods?

I tried diffrent ways to name these methods (like TheClassClosing, HandleClosing, etc.), but i don´t find a good style, to indicate a method as a registered event method. I don´t like the style (underscore) in the generated methods from Visual Studio.

I know that registered event-methods are always private and that there is no naming convention like the one for methods that raise events (aka. OnClosing).

Answer 1

I name my event handlers similarly to those created by Visual Studio (the +,=,tab,tab you mention). I try to keep my naming consistent in my code, and I know that I will be creating handlers with the VS auto-creator at least some of the time.

The underscores don't bother me.

Answer 2

maybe: OnObjectNameEventName, such as

private void OnTheClassClosing(object sender, EventArgs e)

This matches the internal event methods, and with the addition of the object name, it should help differentiate, besides, the method to raise events are essentially internal event handlers

User clicks form, form calls OnClicked, does its thing, then raises the Clicked event, it would only be natural from my point of view.

Answer 3

Name it after what the handler actually does.

// event += event handler
saveButton.Click += SaveData();
startButton.Click += StartTheTimer();

Answer 4

The two common options for naming is either after what the method does:

theObject.Closing += SaveResults;

Or alternatively after what the method handles:

theObject.Closing += ClosingHandler;

Which is preferable really depends a bit on context.

In the first case it is immediately clear what the handler is going to do, which makes the code registering the handler more readable... but looking at the handler SaveResults in isolation it is not going to be necessarily obvious when it is going to be called, unless the event arguments have an obvious name (ClosingEventArgs or some such).

In the second case, the registration is more opaque (okay, so what is going to happen when Closing happens?), but on the other hand, looking at the handler implementation it will be obvious what is going on.

I guess the one to choose depends on which of the two you want to be more obvious; the site of the registration, or the implementation of the handler.

Or alternatively, you can go for the unholy combination of both methods:

theObject.Closing += ClosingHandlerSaveResults;

Now both the registration site and the implementation are equally obvious, and neither looks particularly elegant (plus, it probably violates the DRY principle).

For the record I prefer the first naming scheme when theObject is contained in a different scope from the implementation of SaveResults, and the second scheme when I am wiring up handlers to events that are all contained within the same class.