(.NET Core C#) Add File Attachments to a PDF

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Demonstrates how to attach files to a PDF. This is also known as embedding a file within a PDF.

Note: This example requires Chilkat v9.5.0.97 or greater.

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// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

Chilkat.Pdf pdf = new Chilkat.Pdf();

// We'll be adding attachments to this PDF file..
// Note: We are loading the PDF file into memory.  The PDF file is not kept open at this point.
bool success = pdf.LoadFile("qa_data/pdf/helloWorld.pdf");
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

// Note: The ability to attach files to a PDF was added in Chilkat v9.5.0.97

// Build JSON to provide information about the files to be embedded in the PDF.
Chilkat.JsonObject json = new Chilkat.JsonObject();
json.EmitCompact = false;

int i = 0;

// We can attach multiple files in one operation.

// Here we specify the local relative file path of the 1st file to be embedded.
json.I = i;
json.UpdateString("files[i].description","Hello World");
json.UpdateString("files[i].localFilePath","qa_data/xml/helloWorld.xml");
i = i + 1;

// Specify the 2nd file to be attached.
json.I = i;
json.UpdateString("files[i].description","Image of starfish");
json.UpdateString("files[i].localFilePath","qa_data/jpg/starfish.jpg");
// You can explicitly specify the subType (i.e. MIME type) of the file.
// Otherwise Chilkat will use the default MIME type based on the filename extension.
// If no default MIME type exists, then "application/octet-stream" is used.
json.UpdateString("files[i].subType","image/jpeg");
i = i + 1;

// You can alternatively provide the file data from base64 encoded data rather than from a local file.
json.I = i;
json.UpdateString("files[i].description","Hello World from Data");
json.UpdateString("files[i].fileData","SGVsbG8gV29ybGQsIEhlbGxvIFdvcmxkLCBIZWxsbyBXb3JsZCwgSGVsbG8gV29ybGQsIEhlbGxvIFdvcmxk");
json.UpdateString("files[i].embeddedFilename","abc.txt");
i = i + 1;

// By default, the filename used within the PDF is the filename part of the local file path.
// You can change it by specifying the embeddedFilename.
json.I = i;
json.UpdateString("files[i].description","Invoice");
json.UpdateString("files[i].localFilePath","qa_data/xml/invoice.xml");
json.UpdateString("files[i].embeddedFilename","invoice_1234.xml");
json.UpdateString("files[i].subType","application/xml");

// The above JSON provides instructions for attaching 4 files to the PDF.
// Let's attach the files..
// It is perfectly acceptable to write over the PDF file that was loaded,
// but in this example we'll write the PDF with attachments to a new PDF file.
success = pdf.AddEmbeddedFiles(json,"qa_output/helloWorld_withAttachments.pdf");
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

// You can alternatively write the PDF file with attachments to a Chilkat BinData object..
Chilkat.BinData bd = new Chilkat.BinData();
success = pdf.AddEmbeddedFilesBd(json,bd);
if (success == false) {
    Debug.WriteLine(pdf.LastErrorText);
    return;
}

// Then you can do what you want with the BinData, which contains the binary image of the PDF with attachments.

Debug.WriteLine("Success.");