Sign with Digital Signature

Wordize Signature for .NET allows you to work with the digital signature in the document. You can sign a document or remove a digital signature.

Supported Modules and Document Formats

Use the Wordize Signature for .NET module to work with the digital signature in the document.

Please note that Wordize Signature for .NET currently only supports DOC, DOT, DOCX, DOTX, DOCM, ODT, OTT, and XPS formats. Select document conversion modules to work with the required formats.

Wordize allows users to digitally sign documents, ensuring their authenticity and integrity. A digital signature verifies that the document has not been altered after signing and confirms the signer’s identity. This feature is essential for legal documents, contracts, and other sensitive files.

With Wordize Signature for .NET, you can:

Sign documents programmatically
Remove signatures when needed
Work with cryptographic standards for secure signing

Sign a Document

To sign a document with a digital signature, use the Sign method and the CertificateHolder digital certificate.

CertificateHolder is a digital certificate that follows the internationally accepted X.509 PKI standard, ensuring the public key within the certificate is linked to the signer included inside the certificate.

The following code examples show how to add a digital signature to a document using one of the Sign methods:

method Sign(string, string, CertificateHolder)

CertificateHolder holder = CertificateHolder.Create("morzal.pfx", "wordize");

Signer.Sign("Document.docx", "SignedDocument.1.docx", holder);

method Sign(Stream, Stream, CertificateHolder)

CertificateHolder holder = CertificateHolder.Create("morzal.pfx", "wordize");

using var streamIn = File.OpenRead("Document.docx");
using var streamOut = File.Create("SignedDocument.2.docx");

Signer.Sign(streamIn, streamOut, holder);

Sign a Document Using Sign Options

In addition to the X.509 digital certificate, you can specify the document signing options using the following properties of the SignOptions class:

Comments – to add a comment to your sign
SignTime – to add the date of signing
DecryptionPassword – to add a password to decrypt the source document
ProviderId – to specify the signature provider class ID
XmlDsigLevel – to specify the digital signature level based on the XML-DSig standard

The following code examples show how to digitally sign a document, specifying sign options and using one of the Sign methods:

method Sign(string, string, CertificateHolder, SignOptions)

SignOptions signOptions = new SignOptions();
signOptions.Comments = "My Signature";
signOptions.SignTime = DateTime.Now;
CertificateHolder holder = CertificateHolder.Create("morzal.pfx", "wordize");

Signer.Sign("Document.docx", "SignedDocument.3.docx", holder, signOptions);

method Sign(Stream, Stream, CertificateHolder, SignOptions)

SignOptions signOptions = new SignOptions();
signOptions.Comments = "My Signature";
signOptions.SignTime = DateTime.Now;
CertificateHolder holder = CertificateHolder.Create("morzal.pfx", "wordize");

using var streamIn = File.OpenRead("Document.docx");
using var streamOut = File.Create("SignedDocument.4.docx");

Signer.Sign(streamIn, streamOut, holder);

Remove a Digital Signature

If you need to remove digital signatures from a document, use one of the RemoveAllSignatures methods:

method RemoveAllSignatures(string, string)

Signer.RemoveAllSignatures("SignedDocument.docx", "UnsignedDocument.docx");

method RemoveAllSignatures(Stream, Stream)

using var streamIn = File.OpenRead("SignedDocument.docx");
using var streamOut = File.Create("UnsignedDocument.docx");

Signer.RemoveAllSignatures(streamIn, streamOut);