Go Requires Chilkat v11.7.0+

A PDF Watermark That Only Appears When Printed

See more PDF Watermark Examples

Demonstrates a watermark that is invisible on screen and appears on paper, which is what a "printed copies are uncontrolled" marking needs. Two approaches can do it: an optional-content layer with layer.view off and layer.print on, which also gives the reader an entry in the layers panel of the viewer (layer.locked stops them switching it), and a Watermark annotation with annotation.view false and annotation.print true. annotation.fixedPrint keeps the printed size and position the same whatever paper it goes on. 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 is available at two_page_memo.pdf

    pdf := chilkat.NewPdf()
    success = pdf.LoadFile("qa_data/pdf/two_page_memo.pdf")
    if success == false {
        fmt.Println(pdf.LastErrorText())
        pdf.DisposePdf()
        return
    }

    json := chilkat.NewJsonObject()
    json.UpdateString("type","text")
    json.UpdateString("text","UNCONTROLLED WHEN PRINTED")
    json.UpdateString("id","printonly")

    //  As a layer: off on screen, on when printing, and locked so the reader cannot switch it on.
    json.UpdateString("approach","layer")
    json.UpdateString("layer.name","Print marking")
    json.UpdateString("layer.view","off")
    json.UpdateString("layer.print","on")
    json.UpdateBool("layer.locked",true)

    json.UpdateString("rotation","diagonal")
    json.UpdateString("scale.fit","page")
    json.UpdateNumber("scale.fitPercent","70")
    json.UpdateNumber("opacity","0.3")

    jsonOut := chilkat.NewJsonObject()
    success = pdf.Watermark("add",json,jsonOut)
    if success == false {
        fmt.Println(pdf.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        return
    }

    fmt.Println("layer id: ", *jsonOut.StringOf("id"), " pages: ", *jsonOut.StringOf("pages"))

    success = pdf.WriteFile("qa_output/memo_print_only.pdf")
    if success == false {
        fmt.Println(pdf.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        return
    }

    //  The same thing as an annotation instead.
    pdf2 := chilkat.NewPdf()
    success = pdf2.LoadFile("qa_data/pdf/two_page_memo.pdf")
    if success == false {
        fmt.Println(pdf2.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        pdf2.DisposePdf()
        return
    }

    json2 := chilkat.NewJsonObject()
    json2.UpdateString("type","text")
    json2.UpdateString("text","UNCONTROLLED WHEN PRINTED")
    json2.UpdateString("id","printonly2")
    json2.UpdateString("approach","annotation")
    json2.UpdateBool("annotation.view",false)
    json2.UpdateBool("annotation.print",true)
    json2.UpdateBool("annotation.fixedPrint",true)
    json2.UpdateString("rotation","diagonal")
    success = pdf2.Watermark("add",json2,jsonOut)
    if success == false {
        fmt.Println(pdf2.LastErrorText())
        pdf.DisposePdf()
        json.DisposeJsonObject()
        jsonOut.DisposeJsonObject()
        pdf2.DisposePdf()
        json2.DisposeJsonObject()
        return
    }

    fmt.Println("annotation id: ", *jsonOut.StringOf("id"))

    //  Sample output:

    //  layer id: printonly pages: 1-2
    //  annotation id: printonly2

    pdf.DisposePdf()
    json.DisposeJsonObject()
    jsonOut.DisposeJsonObject()
    pdf2.DisposePdf()
    json2.DisposeJsonObject()