How do I create a digital signature annotation and set its appearance?

[Support]

Q: I need a sample of how to create a signature and set its appearance
stream.
I will populate the signature data, but I need to create a signature
annotation and set its appearance (to a scanned image of a signature)

Can you provide me with a sample?

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A: Sample code to create a digital signature and set its appearance:

Field sig = doc.FieldCreate("sig", Field.Type.e_signature);
pdftron.PDF.Annots.Widget a = pdftron.PDF.Annots.Widget.Create(sdfdoc,
new Rect(50, 550, 350, 600), sig); a.SetAppearance
(CreateSignatureAppearance(doc));
page.AnnotPushBack(a);

static Obj CreateSignatureAppearance(PDFDoc doc)
{
ElementBuilder b = new ElementBuilder();
ElementWriter w = new ElementWriter();
w.Begin(doc);

pdftron.PDF.Image img = pdftron.PDF.Image.Create(doc,
"signature.png");
int width = img.GetImageWidth();
int height = img.GetImageHeight();
Element img_element = b.CreateImage(img, 0, 0, width, height);
w.WritePlacedElement(img_element);

Obj stm = w.End();

// Set the bounding box
stm.PutRect("BBox", 0, 0, width, height);
stm.PutName("Subtype", "Form");

w.Dispose();
b.Dispose();

return stm;
}

You can see a digital signature annotation when viewing the file in
Acrobat. In order to see the image you need to switch off 'Highlight
Fields' option in the upper right corner.