add password in a pdf file using vb.net - vb.net

Question

i just want to ask how can i add a password on a existing PDF file, i just created a pdf file using crystal reports and i kinda need to add some security features for the report. Thank you very much in advance.
lets say the file "c:\Folder1\sample.pdf" already exist. i have seen codes like the one below, but i don't know if it works because i don't know what to add in my reference to make it work
' Define input and output files path.
Dim intputFilePath As String = Program.RootPath + "\\" + "1.pdf"
Dim outputFilePath As String = Program.RootPath + "\\" + "1_with_pw.pdf"
' Set passwords for user and owner.
Dim userPassword As String = "you"
Dim ownerPassword As String = "me"
' Create password setting.
Dim setting As PasswordSetting = New PasswordSetting(userPassword, ownerPassword)
' Add password to plain PDF file and output a new file.
Dim errorCode As Integer = PDFDocument.AddPassword(intputFilePath, outputFilePath, setting)
If errorCode = 0 Then
Console.WriteLine("Success")
Else
Console.WriteLine("Failed")
End If

Answer 1

Dim WorkingFolder As String = Environment.GetFolderPath(Environment.SpecialFolder.Desktop)
Dim InputFile As String = Path.Combine(WorkingFolder, "PSNOs.pdf")
Dim OutputFile As String = Path.Combine(WorkingFolder, "PSNOs_enc.pdf")
Using input As Stream = New FileStream(InputFile, FileMode.Open, FileAccess.Read, FileShare.Read)
Using output As Stream = New FileStream(OutputFile, FileMode.Create, FileAccess.Write, FileShare.None)
Dim reader As New PdfReader(input)
PdfEncryptor.Encrypt(reader, output, True, Nothing, "secret", PdfWriter.ALLOW_SCREENREADERS)
End Using
End Using
the word "PdfReader" have an error message but it doesn't ask to import something..