VB.NET Requires Chilkat v11.7.0+
VB.NET
PDF Owner Password vs. User Password
See more PDF Protection Examples
Demonstrates the difference between the two passwords of an encrypted PDF. Either one opens the file. The user password gives the rights the permissions grant. The owner password gives owner rights: no restriction applies, and it is the only one that lets the security be changed or removed. Every Protection operation except getInfo needs owner rights, and Chilkat does not offer a way around that.Chilkat VB.NET Downloads
Dim success As Boolean = False
' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.
' The PDF used in this example is available at encrypted_user_password.pdf
Dim json As New Chilkat.JsonObject
Dim jsonOut As New Chilkat.JsonObject
' Opened with the user password.
Dim user As New Chilkat.Pdf
user.UserPassword = "secret"
success = user.LoadFile("qa_data/pdf/encrypted_user_password.pdf")
If (success = False) Then
Debug.WriteLine(user.LastErrorText)
Exit Sub
End If
success = user.Protection("getInfo",json,jsonOut)
If (success = False) Then
Debug.WriteLine(user.LastErrorText)
Exit Sub
End If
Debug.WriteLine("opened with: " & jsonOut.StringOf("loaded.openedWith"))
' Changing the security needs owner rights, so this is refused.
success = user.Protection("removeEncryption",json,jsonOut)
If (success = False) Then
Debug.WriteLine("removeEncryption was refused: the PDF was not opened with its owner password.")
End If
' Opened with the owner password.
Dim owner As New Chilkat.Pdf
owner.OwnerPassword = "owner-secret"
success = owner.LoadFile("qa_data/pdf/encrypted_user_password.pdf")
If (success = False) Then
Debug.WriteLine(owner.LastErrorText)
Exit Sub
End If
success = owner.Protection("getInfo",json,jsonOut)
If (success = False) Then
Debug.WriteLine(owner.LastErrorText)
Exit Sub
End If
Debug.WriteLine("opened with: " & jsonOut.StringOf("loaded.openedWith"))
' Now it is allowed.
success = owner.Protection("removeEncryption",json,jsonOut)
If (success = False) Then
Debug.WriteLine(owner.LastErrorText)
Exit Sub
End If
Debug.WriteLine("removeEncryption succeeded; will be saved encrypted: " & jsonOut.BoolOf("pending.encrypted"))
' Sample output:
' opened with: user
' removeEncryption was refused: the PDF was not opened with its owner password.
' opened with: owner
' removeEncryption succeeded; will be saved encrypted: False