Difference between event Action and event EventHandler

Question

What is the problem when declaring events with Action

public interface ISomething
{
    event Action MyEventName;
}

or

public interface ISomething
{
    event Action<bool> MyBoolEventName;
}

instead of the other variant of the previous code declaring events with EventHandler and EventArgs

public interface ISomething
{
     event EventHandler<EventArgs> MyEventName;
}

or

public class EventArgsWithBool : EventArgs
{
    private readonly bool someValue;

    public EventArgsWithBool (bool someValue)
    {
        this.someValue = someValue;
    }

    public bool SomeValue
    {
        get { return this.someValue; }
    }
}

public interface ISomething
{
     event EventHandler<EventArgsWithBool> MyBoolEventName;
}

My thoughts:

Both versions work fine for me and I think the first one is more readable / looks more direct to the point. But some developers say it is better to use the 2nd syntax with EventArgs without being able to give good technical reasons why (other than they know the 2nd syntax).

Are there any technical problems to face when using the first one?

http://stackoverflow.com/questions/1431359/event-action-vs-event-eventhandler — Alexander Balabin, Jul 07 '15 at 16:18

score 2 · Accepted Answer · answered Jul 07 '15 at 19:39

2

When you use Action, you are not passing the Sender object to the event handler. Sometimes it is useful for the event handler to know what object triggered the event.

answered Jul 07 '15 at 19:39

Dwedit

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1

I could also use Action and set it explicitely, but you're right in this case. – Beachwalker Jul 08 '15 at 15:15

Difference between event Action and event EventHandler

1 Answers1