Swift Requires Chilkat v11.7.0+

Replace the Second (or Every) Occurrence of a Label in a PDF

See more PDF Text Replacement Examples

Demonstrates the "occurrence" member of a label entry. By default the first occurrence of a label, in reading order across the selected pages, is replaced; "occurrence" can be a number for the nth, or "all" for every occurrence. The invoice template has "Ref:" twice. Swift

func chilkatTest() {
    var success: Bool = 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 invoice_template.pdf

    let pdf = CkoPdf()!
    success = pdf.loadFile(filePath: "qa_data/pdf/invoice_template.pdf")
    if success == false {
        print("\(pdf.lastErrorText!)")
        return
    }

    let json = CkoJsonObject()!
    let jsonOut = CkoJsonObject()!

    //  This template's {{placeholders}} are not being filled here: "keep" leaves them as they are
    //  (the default, "error", would refuse to apply while a placeholder on the page has no value).
    json.updateString(jsonPath: "unusedPlaceholders", value: "keep")

    //  "Ref:" appears twice on the page (A-1 near the top, A-2 below the totals).
    //  The default replaces the first occurrence only.
    json.updateString(jsonPath: "labels[0].label", value: "Ref:")
    json.updateString(jsonPath: "labels[0].value", value: "B-7")
    success = pdf.textReplace(op: "check", jsonIn: json, jsonOut: jsonOut)
    if success == false {
        print("\(pdf.lastErrorText!)")
        return
    }

    print("default: \(jsonOut.int(of: "replacements[0].count").intValue) occurrence replaced")

    //  The second occurrence only.
    json.updateString(jsonPath: "labels[0].occurrence", value: "2")
    success = pdf.textReplace(op: "check", jsonIn: json, jsonOut: jsonOut)
    if success == false {
        print("\(pdf.lastErrorText!)")
        return
    }

    print("occurrence 2: \(jsonOut.int(of: "replacements[0].count").intValue) occurrence replaced")

    //  Every occurrence.
    json.updateString(jsonPath: "labels[0].occurrence", value: "all")
    success = pdf.textReplace(op: "apply", jsonIn: json, jsonOut: jsonOut)
    if success == false {
        print("\(pdf.lastErrorText!)")
        return
    }

    print("occurrence all: \(jsonOut.int(of: "replacements[0].count").intValue) occurrences replaced")

    success = pdf.writeFile(path: "qa_output/invoice_refs.pdf")
    if success == false {
        print("\(pdf.lastErrorText!)")
        return
    }

    //  Sample output:

    //  default: 1 occurrence replaced
    //  occurrence 2: 1 occurrence replaced
    //  occurrence all: 2 occurrences replaced

}