Returns a PdfAnnots collection of PdfAnnot objects representing individual top-level form fields.

Returns or specifies a flag controlling whether to construct appearances for all form fields in the document. False by default.

Returns or specifies signature flags. The following flag bits are defined:

Bit 1: If set, the document contains at least one signature field.
Bit 2: If set, the document contains signatures that may be invalidated if the file is saved (written) in a way that alters its previous contents (such as with the "optimize" option). Merely updating the file by appending new information to the end of the previous version is safe.