Calling an event handler manually [duplicate]

Question

I have an event handler method that's called directly as a standard method. That is, it's not only called when my event occurs but also just as a private method.

UtilStk.StkRoot.OnStkObjectAdded += new 
    IAgStkObjectRootEvents_OnStkObjectAddedEventHandler(TallyScenarioObjects);

private void TallyScenarioObjects(object sender)
{
    ...
}

Is it suitable to pass a null argument when calling this handler directly?

TallyScenarioObjects(null);

Answer 1

Just encapsulate the common logic into another method that can be called from your event handler:

UtilStk.StkRoot.OnStkObjectAdded += new IAgStkObjectRootEvents_OnStkObjectAddedEventHandler(TallyScenarioObjects);

private void TallyScenarioObjects(object sender)
{
    DoStuff();
}

private void DoStuff() { ... }

private void AnotherMethod()
{
    DoStuff();
}

That said, your handler is a method, there's nothing special about it, so you could always dummy up arguments and call it directly. I wouldn't go that route though.

Answer 2

Yes that would work, but it would be better practice to have a 2nd method that could be called directly or from the event handler:

UtilStk.StkRoot.OnStkObjectAdded += new IAgStkObjectRootEvents_OnStkObjectAddedEventHandler(TallyScenarioObjects);

private void TallyScenarioObjects(object sender)
{
     DoTally(....);
}

private void DoTally(....)
{
}

If nothing else you won't confuse other developers who won't be expecting to see an event handler called that way.