If the selected document has been encrypted this function returns the encryption strength. This is the length of the key used to encrypt the contents of the document.
function TDebenuPDFLibrary1511.EncryptionStrength: Integer;
Function DebenuPDFLibrary1511.PDFLibrary::EncryptionStrength As Long
int DPLEncryptionStrength(int InstanceID)
|0||The selected document is not encrypted|
|40||The document has been encrypted with 40-bit encryption (Adobe Acrobat 3.x and 4.x)|
|128||The document has been encrypted with 128-bit encryption (Adobe Acrobat 5.x)|
|256||The document has been encrypted with 256-bit encryption (Acrobat 9 or Acrobat 10). Use the SecurityInfo function to determine which version of encryption was used.|