ImageGear for .NET has limited support for PDF documents containing XFA forms.

By default, loading a PDF document that contains XFA data will throw an exception and the document will not be loaded since special consideration is needed on how to treat such a document (see below).

In order to enable opening of PDF documents containing XFA data, you have to set the corresponding control parameter XFAAllowed to true:

IImGearFormat format = ImGearFileFormats.Filters.Get(ImGearFormats.PDF);
format.Parameters.GetByName("XFAAllowed").Value = true;

PDF documents containing XFA come in different flavors: dynamic and static. Currently, ImageGear for .NET does not support rendering of dynamic XFA content. Usually, a placeholder page with a warning message that is present in the document will be rendered instead. Documents containing static XFA will usually render correctly since the XFA information is duplicated in the PDF as Acroform fields and/or content, and XFA data is simply ignored.

Since XFA data is currently largely ignored by ImageGear .NET, changing form fields by means of the ImGearPDFDocument.Form and related objects will not update the XFA data, and these will become out of sync with the Acroforms data. Fields and their widgets should therefore not be added, removed, modified, flattened or filled in.

The only valid operation on a form when XFA is present is the flattening of the whole form using ImGearPDFDocument.FlattenFormFields(). This will flatten any Acroform fields and remove the Form, including any XFA data.