C# Requires Chilkat v11.7.0+

Replace PDF Text on Selected Pages Only

See more PDF Text Replacement Examples

Demonstrates the "pages" option, which limits the search for placeholders and labels to the given pages: "all" (the default), "first", "last", "odd", "even", or a list such as "1,3,5-9". The two-page order confirmation carries the same "Status:" label on both pages; the status is changed on page 2 only, then on both pages. C#

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 is available at order_confirmation.pdf

Chilkat.Pdf pdf = new Chilkat.Pdf();
success = pdf.LoadFile("qa_data/pdf/order_confirmation.pdf");
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Chilkat.JsonObject json = new Chilkat.JsonObject();
Chilkat.JsonObject jsonOut = new Chilkat.JsonObject();

//  Both pages have "Status:   Pending".  With pages "2", only page 2 is searched.
json.UpdateString("pages","2");
json.UpdateString("labels[0].label","Status:");
json.UpdateString("labels[0].value","Shipped");
success = pdf.TextReplace("check",json,jsonOut);
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Debug.WriteLine("pages 2: found on page(s) " + jsonOut.StringOf("replacements[0].pages"));

//  With every page searched, the default occurrence ("first") still replaces one -- the first in reading order.
json.UpdateString("pages","all");
success = pdf.TextReplace("check",json,jsonOut);
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Debug.WriteLine("pages all, first occurrence: found on page(s) " + jsonOut.StringOf("replacements[0].pages"));

//  Every occurrence on every page.
json.UpdateString("labels[0].occurrence","all");
success = pdf.TextReplace("apply",json,jsonOut);
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Debug.WriteLine("pages all, every occurrence: " + Convert.ToString(jsonOut.IntOf("replacements[0].count")) + " replaced on page(s) " + jsonOut.StringOf("replacements[0].pages"));

success = pdf.WriteFile("qa_output/order_shipped.pdf");
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

//  Sample output:

//  pages 2: found on page(s) 2
//  pages all, first occurrence: found on page(s) 1
//  pages all, every occurrence: 2 replaced on page(s) 1,2