event Event (EventID as Long)
Notifies the application once the control fires an event.

TypeDescription
EventID as Long A Long expression that specifies the identifier of the event. Each internal event of the control has an unique identifier. Use the EventParam(-2) to display entire information about fired event ( such as name, identifier, and properties ). The EventParam(-1) retrieves the number of parameters of fired event
The Event notification occurs ANY time the control fires an event. This is useful for X++, which does not support event with parameters passed by reference. Also, this could be useful for C++ Builder or Delphi, which does not handle properly the events with parameters of VARIANT type.

In X++ the "Error executing code: FormActiveXControl (data source), method ... called with invalid parameters" occurs when handling events that have parameters passed by reference. Passed by reference, means that in the event handler, you can change the value for that parameter, and so the control will takes the new value, and use it. The X++ is NOT able to handle properly events with parameters by reference, so we have the solution. 

The solution is using and handling the Event notification and EventParam method., instead handling the event that gives the "invalid parameters" error executing code.

If you are not familiar with what a type library means just handle the Event of the control as follows:

// Notifies the application once the control fires an event.
void onEvent_Event(int _EventID)
{
	print expivot1.EventParam(-2).toString();
}

This code allows you to display the information for each event of the control being fired as in the list bellow:

"MouseMove/-606( 1 , 0 , 145 , 36 )" VT_BSTR
"BeforeDrawPart/54( 2 , -1962866148 , =0 , =0 , =0 , =0 , =false )" VT_BSTR
"AfterDrawPart/55( 2 , -1962866148 , 0 , 0 , 0 , 0 )" VT_BSTR
"MouseMove/-606( 1 , 0 , 145 , 35 )" VT_BSTR

Each line indicates an event, and the following information is provided:  the name of the event, its identifier, and the list of parameters being passed to the event. The parameters that starts with = character, indicates a parameter by reference, in other words one that can changed during the event handler. 

In conclusion, anytime the X++ fires the "invalid parameters." while handling an event, you can use and handle the Event notification and EventParam methods of the control

Syntax for Event event, /NET version, on:

private void Event(object sender,int EventID)
{
}

Private Sub Event(ByVal sender As System.Object,ByVal EventID As Integer) Handles Event
End Sub

Syntax for Event event, /COM version, on:

private void Event(object sender, AxEXPIVOTLib._IPivotEvents_EventEvent e)
{
}

void OnEvent(long EventID)
{
}

void __fastcall Event(TObject *Sender,long EventID)
{
}

procedure Event(ASender: TObject; EventID : Integer);
begin
end;

procedure Event(sender: System.Object; e: AxEXPIVOTLib._IPivotEvents_EventEvent);
begin
end;

begin event Event(long EventID)
end event Event

Private Sub Event(ByVal sender As System.Object, ByVal e As AxEXPIVOTLib._IPivotEvents_EventEvent) Handles Event
End Sub

Private Sub Event(ByVal EventID As Long)
End Sub

Private Sub Event(ByVal EventID As Long)
End Sub

LPARAMETERS EventID

PROCEDURE OnEvent(oPivot,EventID)
RETURN

Syntax for Event event, /COM version (others), on:

<SCRIPT EVENT="Event(EventID)" LANGUAGE="JScript">
</SCRIPT>

<SCRIPT LANGUAGE="VBScript">
Function Event(EventID)
End Function
</SCRIPT>

Procedure OnComEvent Integer llEventID
	Forward Send OnComEvent llEventID
End_Procedure

METHOD OCX_Event(EventID) CLASS MainDialog
RETURN NIL

void onEvent_Event(int _EventID)
{
}

function Event as v (EventID as N)
end function

function nativeObject_Event(EventID)
return