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Sign a documentkeyboard_arrow_down

Sign a PDF document in C++

To sign an existing approval signature field in a PDF Document:

PDFDoc doc(docpath);

// Retrieve the unsigned approval signature field.
Field found_approval_field(doc.GetField(approval_field_name));
PDF::DigitalSignatureField approval_digsig_field(found_approval_field);

// (OPTIONAL) Add more information to the signature dictionary.
approval_digsig_field.SetLocation("Vancouver, BC");
approval_digsig_field.SetReason("Document approval.");

// (OPTIONAL) Add an appearance to the signature field.
PDF::Image img = PDF::Image::Create(doc, appearance_img_path);
Annots::SignatureWidget approval_signature_widget(found_approval_field.GetSDFObj());

// Prepare the signature and signature handler for signing.
approval_digsig_field.SignOnNextSave(private_key_file_path, keyfile_password);

// The actual approval signing will be done during the following incremental save operation.
doc.Save(outpath, SDFDoc::e_incremental, NULL);

Digitally sign PDF files
Full code sample which demonstrates using the digital signature API to digitally sign and/or certify PDF documents.

linkAbout Adding An Approval Signature to a PDF Document

The PDFTron SDK enables approval signatures in PDF documents using a Digital Certificate, in accordance with the latest PDF specification. By leveraging public key infrastructure (PKI) technology, with a certificate issued by a trusted certificate authority (CA), a signer can use a certificate-based digital ID to guarantee the authenticity of a signature. Placement of a digital signature using a certificate can also guarantee that a document was not modified since the signature was placed, ensuring the authenticity of the document.

Above is an example of a document containing a certified signature, guaranteed by a certificate generated by

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