(Optional) The subtype of the embedded file. The value of this entry must be a first-class name, as defined in Appendix E. Names without a registered prefix must conform to the MIME media type names defined in Internet RFC 2046, Multipurpose Internet Mail Extensions (MIME), Part Two: Media Types(see the Bibliography), with the provision that characters not allowed in names must use the 2-character hexadecimal code format described in Section 3.2.4, “Name Objects.”

public const string Subtype

Public Const Subtype As String

public:
literal String^ Subtype