EmbeddedFile Subtype Property. The subtype of the embedded file. ABCpdf .NET PDF Library. From ABCpdf .net previous page next page Subtype Property Type Default Value Read Only Description [C#] string [Visual Basic] String null No The subtype of the embedded file Notes The subtype of the embedded file. This property is represented via a NameAtom and hence it cannot take an empty string. As such, setting this property to an empty string will set it to null. Example None. previous page start next page