About GroupDocs.Signature for .NET Digital signatures API

GroupDocs.Signature for .NET is a popular API to esign documents with the digital electronic signatures, with digital certificates. For the Digital signatures API uses PFX certificate files to esign document with password protected private and public keys. The Digital signatures might be used to certify business documents with eSign PDF particular page, certify entire Microsoft Office documents like Words, Excel, Powerpoint files, and Open Office documents. Customers can easily manipulate the signatures like editing them, removing or adjust. The API provides a way to search and verify signatures. Moreover, a lot of abilities for signatures customization are provided.

Steps to sign Zip with Digital in C#

GroupDocs.Signature for .NET provides ability to sign Zip documents with Digital signatures quickly and easily.

Create an instance of Signature class providing Zip file supposed to signing as path or memory stream
Instantiate SignOptions class and set all demanded data.
Invoke the Signature.Sign() method passing output Zip file or memory stream

System Requirements

GroupDocs.Signature for .NET are supported on all major platforms and operating systems. Before executing the code below, please make sure that you have the following prerequisites installed on your system.

Operating systems: Microsoft Windows, Linux, MacOS
Development environments: Microsoft Visual Studio, Xamarin, MonoDevelop
Frameworks: .NET Framework, .NET Standard, .NET Core, Mono
Get the latest GroupDocs.Signature for .NET from Nuget

        
// Set up input Zip file
string filePath = "input.zip";
// Set up output file
string outputFilePath = "output.zip";
// Provide digital certificate
string certificateFilePath = "certificate.pfx";

// Instantiate Signature for input file
using (GroupDocs.Signature.Signature signature = new GroupDocs.Signature.Signature(filePath))
{
        //Provide sign options
        DigitalSignOptions options = new DigitalSignOptions(certificateFilePath)
        {
            // set certificate password
            Password = "1234567890",
            // set signature position
            Left = 50,
            Top = 200,
        };

        // sign Zip document
        SignResult result = signature.Sign(outputFilePath, options);
}