C# Requires Chilkat v11.7.0+

Put a Letterhead Behind the First Page of a PDF

See more PDF Watermark Examples

Demonstrates the pdfPage type, which places a page of another PDF as the watermark. It is the way to use a letterhead, a cover overlay or a vector logo that was saved as a PDF, and unlike an image it stays sharp at any size because it is drawn, not resampled. "zOrder" set to back puts it behind the existing content, where a letterhead belongs, and "pages" set to first restricts it to page one. 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 two_page_memo.pdf

//  The PDF used in this example is available at letterhead.pdf

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

Chilkat.JsonObject json = new Chilkat.JsonObject();
json.UpdateString("type","pdfPage");
json.UpdateString("pdf.path","qa_data/pdf/letterhead.pdf");

//  The page of the source PDF to use (1 by default).  "match" instead of a number places source
//  page n on target page n, which suits a set of per-page backgrounds.
json.UpdateInt("pdf.page",1);

//  Behind the memo's own text, on page one, scaled to the page.
json.UpdateString("zOrder","back");
json.UpdateString("pages","first");
json.UpdateString("scale.fit","page");
json.UpdateString("id","letterhead");

Chilkat.JsonObject jsonOut = new Chilkat.JsonObject();
success = pdf.Watermark("add",json,jsonOut);
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

Debug.WriteLine("id: " + jsonOut.StringOf("id") + " pages: " + jsonOut.StringOf("pages"));

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

//  Sample output:

//  id: letterhead pages: 1