VB.NET Requires Chilkat v11.7.0+

Extract Text from a PDF that Forbids Copying

See more PDF Text Extraction Examples

Demonstrates a PDF that opens without a password but whose permissions do not allow copying text. The "text", "markdown", "search" and "tables" operations fail with that reason; "assess" always works. Loading the PDF with the OwnerPassword property set grants owner rights, and extraction works. VB.NET

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 (owner password: owner-secret; copying not permitted) is available at no_copy_permission.pdf

Dim pdf As New Chilkat.Pdf
Dim json As New Chilkat.JsonObject
Dim jsonOut As New Chilkat.JsonObject

'  The PDF opens without a password.
success = pdf.LoadFile("qa_data/pdf/no_copy_permission.pdf")
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If


'  Extracting text is refused, because the PDF's permissions do not allow copying.
success = pdf.ExtractText("text",json,jsonOut)
If (success = False) Then
    Debug.WriteLine("Extraction refused: " & pdf.LastErrorText)
End If


'  "assess" reports only counts and ratings, never text, so it is always allowed.
success = pdf.ExtractText("assess",json,jsonOut)
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If

Debug.WriteLine("rating: " & jsonOut.StringOf("quality.rating"))

'  Load with the owner password to get owner rights, which include copying.
pdf.OwnerPassword = "owner-secret"
success = pdf.LoadFile("qa_data/pdf/no_copy_permission.pdf")
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If


success = pdf.ExtractText("text",json,jsonOut)
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If

Debug.WriteLine(jsonOut.StringOf("text"))

'  Sample output:

'  Extraction refused: ChilkatLog:
'    ExtractText:
'      ...
'        The PDF's permissions do not allow copying or extracting text (load it with the owner password to extract).
'      ...
'  rating: good
'  Visitor Leaflet
'  
'  Welcome to the harbor lighthouse. The tower is open on weekends from July to September.
'  
'  Please keep to the marked paths and do not climb on the breakwater.
'  
'  The lantern room is closed in high winds.