Retrieves the index of the active frame in the frames collection.
One of the values in the Property Values section.
A print template uses this property to find the active frame. Every document that contains an active frame must have this property in order for the template to determine the index of the currently active frame.
This property has no effect on what is printed, but rather reflects the UI in the print dialog so that the template can tell if the user asked to print the active frame.
The following snippet shows how to retrieve the active frame. The snippet assumes a template that contains a LayoutRect called LRect0 with contentSrc = "document" and that the content document is a frameSet that has an active frame.