Go Requires Chilkat v11.7.0+

Extract Text from a Password-Protected PDF

See more PDF Text Extraction Examples

Demonstrates extracting text from a PDF that requires a password to open. The PDF loads without the password (its structure can be read), but the "text" operation fails because the content cannot be decrypted; "assess" reports that a password is required. With the UserPassword property set before loading, extraction works normally. Go

    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 (user password: secret) is available at encrypted_user_password.pdf

    pdf := chilkat.NewPdf()
    json := chilkat.NewJsonObject()
    jsonOut := chilkat.NewJsonObject()

    //  The PDF loads without its password: the file's structure is readable, so properties such as
    //  NumPages and the security settings are available...
    success = pdf.LoadFile("qa_data/pdf/encrypted_user_password.pdf")
    if success == false {
        fmt.Println(pdf.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        return
    }

    //  ...but the content cannot be decrypted, so extracting text fails.
    success = pdf.ExtractText("text",json,jsonOut)
    if success == false {
        fmt.Println("Cannot extract: ", pdf.LastErrorText())
    }

    //  "assess" still works: it reports that a password is required and nothing else.
    success = pdf.ExtractText("assess",json,jsonOut)
    if success == false {
        fmt.Println(pdf.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        return
    }

    fmt.Println("passwordRequired: ", *jsonOut.BoolOf("quality.passwordRequired"))
    fmt.Println("rating: ", *jsonOut.StringOf("quality.rating"))

    //  Set the password and load again.
    pdf.SetUserPassword("secret")
    success = pdf.LoadFile("qa_data/pdf/encrypted_user_password.pdf")
    if success == false {
        fmt.Println(pdf.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        return
    }

    success = pdf.ExtractText("text",json,jsonOut)
    if success == false {
        fmt.Println(pdf.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        return
    }

    fmt.Println(*jsonOut.StringOf("text"))

    //  Sample output:

    //  Cannot extract: ChilkatLog:
    //    ExtractText:
    //      ...
    //        The PDF is encrypted and could not be opened (wrong or missing password); its text cannot be read.
    //      ...
    //  passwordRequired: true
    //  rating: none
    //  Board Minutes (Confidential)
    //  
    //  The board met on 3 November 2026. Present: the chair, the treasurer and four members. The treasurer reported that spending for the season came in under budget.
    //  
    //  The meeting closed at 8.45 p.m.

    pdf.DisposePdf()
    json.DisposeJsonObject()
    jsonOut.DisposeJsonObject()