C# Requires Chilkat v11.7.0+
C#
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.Chilkat C# Downloads
bool success = 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
Chilkat.Pdf pdf = new Chilkat.Pdf();
Chilkat.JsonObject json = new Chilkat.JsonObject();
Chilkat.JsonObject jsonOut = new Chilkat.JsonObject();
// The PDF opens without a password.
success = pdf.LoadFile("qa_data/pdf/no_copy_permission.pdf");
if (success == false) {
Debug.WriteLine(pdf.LastErrorText);
return;
}
// Extracting text is refused, because the PDF's permissions do not allow copying.
success = pdf.ExtractText("text",json,jsonOut);
if (success == false) {
Debug.WriteLine("Extraction refused: " + pdf.LastErrorText);
}
// "assess" reports only counts and ratings, never text, so it is always allowed.
success = pdf.ExtractText("assess",json,jsonOut);
if (success == false) {
Debug.WriteLine(pdf.LastErrorText);
return;
}
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) {
Debug.WriteLine(pdf.LastErrorText);
return;
}
success = pdf.ExtractText("text",json,jsonOut);
if (success == false) {
Debug.WriteLine(pdf.LastErrorText);
return;
}
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.