The PdfPasswordEncryption type exposes the following members.
Gets or sets the Document Open password (also known as a user password) required to open the PDF file.
Default value: Empty (PDF file can be decrypted without a password).
Gets or sets the encryption level.
Default value: AES_128.
Gets or sets the encryption options.
Default value: EncryptAll.
(Required) A set of flags specifying which operations shall be permitted when the document is opened with user access (see Table 22).