This class represents the form field additional-actions dictionary. This is definitively detailed in:.

The ISO PDF Specification, ISO 32000-1:2008 PDF 1.7; Table: 196, page 416.

The ISO PDF Specification, ISO 32000-2:2017 PDF 2.0; Table: 199, page 505.

System.Object
    WebSupergoo.ABCpdf14.Elements.Element
       WebSupergoo.ABCpdf14.Elements.FormFieldAdditionalActionsElement

A form field additional-actions dictionary associates actions with keystroke, format, validate, and calculate events during interaction with a form field.

The K (keystroke) action fires as the user types before the value is committed. The F (format) action fires after commit to control display formatting. The V (validate) action fires on focus loss. The C (calculate) action fires during the document's recalculation pass.