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There are three basic characteristics used to manipulate
an ActiveX Control’s functionality: Methods,
Properties, and Events. Not all ActiveX
Controls have all three characteristics; the attributes
of ActiveX Controls vary from control to control.
It is important to know the characteristics, abilities,
and restrictions of an ActiveX Control so that the Control
will work as intended and to its fullest potential.
Method: The function(s) an ActiveX Control can
perform(s)
For example, an audio ActiveX might have the functions
of Play, Play Once, and Stop.
Note: Methods are invoked, or called, by using the
Call ActiveX Method ScriptItem.
Property: The feature(s) of an ActiveX Control
For example, one of the AutomatedGIF ActiveX properties
is the AnimatedGif[PropGet] which identifies the gif
being used in the animation.
Note: A Property is set by using the Set Property
ScriptItem not by the Call ActiveX Method ScriptItem.
Event: The action item which fires the ActiveX
Control
For example, the slider handle on a Slider ActiveX
Control is one of its Events.
Note: An ActiveX can have both user
and non-user Events, the events are specific to the
Control being used. Also, the default Events used by
Objects (OnMouseIn, OnMouseOut, OnMouseDown, OnMouseUp)
might not be specific to an ActiveX Control. However,
an Objects’ Events can Call an
ActiveX Method and trigger the Control.
Parameter: Some ActiveX Controls require an
argument (modifier, switch) to enable performance.
For example, an ActiveX Control associated with displaying
a .gif file would need the name and location of the
.gif file in order to display the .gif. The name and
location of the .gif file is the Parameter.
Return Value – Some ActiveX Controls may
return information when a Method is called or a Property
is set. This return information is called a Return Value
and can be any variable type. Not all Controls support
Return Values, they are specific to the control, method,
and property of an ActiveX as well as to the way the
Control was written. In general, a Return Value is an
acknowledgement of what took place when a Method or
Property was invoked. The information returned can be
used to trigger any number of actions.
For example: a Method is called to Play an .mp3 file,
a successful Return Value might be used to display the
artist of the .mp3 while the song plays, an unsuccessful
Return Value might be used to display a dialog box "Can
not find file, please try again."
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