Class DigitalSignatureCollection

DigitalSignatureCollection class

Provides a collection of digital signatures attached to a document.

public class DigitalSignatureCollection : IEnumerable

Constructors

NameDescription
DigitalSignatureCollection()The constructor of DigitalSignatureCollection.

Methods

NameDescription
Add(DigitalSignature)Add one signature to DigitalSignatureCollection.
GetEnumerator()Get the enumerator for DigitalSignatureCollection, this enumerator allows iteration over the collection

Examples

namespace AsposeCellsExamples
{
    using Aspose.Cells;
    using Aspose.Cells.DigitalSignatures;
    using System;
    using System.Security.Cryptography.X509Certificates;

    public class DigitalSignatureCollectionDemo
    {
        public static void DigitalSignatureCollectionExample()
        {
            // Load a workbook from a signed source file
            Workbook signedWorkbook = new Workbook(@"DigitalSignatureCollection_original.xlsx");

            // Check if the workbook is digitally signed
            Console.WriteLine("Is the workbook digitally signed? " + signedWorkbook.IsDigitallySigned);

            // Get the digital signature collection from the workbook
            DigitalSignatureCollection existingDsc = signedWorkbook.GetDigitalSignature();

            if (existingDsc != null)
            {
                // Iterate over the digital signatures in the collection
                foreach (DigitalSignature existingDs in existingDsc)
                {
                    Console.WriteLine("Comments: " + existingDs.Comments);
                    Console.WriteLine("Sign Time: " + existingDs.SignTime);
                    Console.WriteLine("Is Valid: " + existingDs.IsValid);
                }

                // Create a new digital signature
                X509Certificate2 certificate = new X509Certificate2("path_to_certificate.pfx", "password");
                DigitalSignature newSignature = new DigitalSignature(certificate, "New signature comment", DateTime.Now);

                // Add the new digital signature to the collection
                existingDsc.Add(newSignature);
            }     
            

            // Save the workbook with the new digital signature
            signedWorkbook.Save("DigitalSignatureCollectionExample.xlsx");
            signedWorkbook.Save("DigitalSignatureCollectionExample.pdf");
            return;
        }
    }
}

See Also