DigitalSignatures

Document.DigitalSignatures property

Gets the collection of digital signatures for this document and their validation results.

public DigitalSignatureCollection DigitalSignatures { get; }

Remarks

This collection contains digital signatures that were loaded from the original document. These digital signatures will not be saved when you save this Document object into a file or stream because saving or converting will produce a document that is different from the original and the original digital signatures will no longer be valid.

This collection is never null. If the document is not signed, it will contain zero elements.

Examples

Shows how to validate and display information about each signature in a document.

Document doc = new Document(MyDir + "Digitally signed.docx");

foreach (DigitalSignature signature in doc.DigitalSignatures)
{
    Console.WriteLine($"{(signature.IsValid ? "Valid" : "Invalid")} signature: ");
    Console.WriteLine($"\tReason:\t{signature.Comments}");
    Console.WriteLine($"\tType:\t{signature.SignatureType}");
    Console.WriteLine($"\tSign time:\t{signature.SignTime}");
    Console.WriteLine($"\tSubject name:\t{signature.CertificateHolder.Certificate.SubjectName}");
    Console.WriteLine($"\tIssuer name:\t{signature.CertificateHolder.Certificate.IssuerName.Name}");
    Console.WriteLine();
}

Shows how to sign documents with X.509 certificates.

// Verify that a document is not signed.
Assert.That(FileFormatUtil.DetectFileFormat(MyDir + "Document.docx").HasDigitalSignature, Is.False);

// Create a CertificateHolder object from a PKCS12 file, which we will use to sign the document.
CertificateHolder certificateHolder = CertificateHolder.Create(MyDir + "morzal.pfx", "aw", null);

// There are two ways of saving a signed copy of a document to the local file system:
// 1 - Designate a document by a local system filename and save a signed copy at a location specified by another filename.
SignOptions signOptions = new SignOptions { SignTime = DateTime.Now };
DigitalSignatureUtil.Sign(MyDir + "Document.docx", ArtifactsDir + "Document.DigitalSignature.docx",
    certificateHolder, signOptions);

Assert.That(FileFormatUtil.DetectFileFormat(ArtifactsDir + "Document.DigitalSignature.docx").HasDigitalSignature, Is.True);

// 2 - Take a document from a stream and save a signed copy to another stream.
using (FileStream inDoc = new FileStream(MyDir + "Document.docx", FileMode.Open))
{
    using (FileStream outDoc = new FileStream(ArtifactsDir + "Document.DigitalSignature.docx", FileMode.Create))
    {
        DigitalSignatureUtil.Sign(inDoc, outDoc, certificateHolder);
    }
}

Assert.That(FileFormatUtil.DetectFileFormat(ArtifactsDir + "Document.DigitalSignature.docx").HasDigitalSignature, Is.True);

// Please verify that all of the document's digital signatures are valid and check their details.
Document signedDoc = new Document(ArtifactsDir + "Document.DigitalSignature.docx");
DigitalSignatureCollection digitalSignatureCollection = signedDoc.DigitalSignatures;

Assert.That(digitalSignatureCollection.IsValid, Is.True);
Assert.That(digitalSignatureCollection.Count, Is.EqualTo(1));
Assert.That(digitalSignatureCollection[0].SignatureType, Is.EqualTo(DigitalSignatureType.XmlDsig));
Assert.That(signedDoc.DigitalSignatures[0].IssuerName, Is.EqualTo("CN=Morzal.Me"));
Assert.That(signedDoc.DigitalSignatures[0].SubjectName, Is.EqualTo("CN=Morzal.Me"));

See Also

Document.DefaultTabStop Document.EndnoteOptions