GroupDocs.Signature for .NET is a comprehensive library that allows you to sign PDF, Word, Excel, JPG, and Presentation documents using various electronic signatures like text, image, barcode, QR code, metadata, form field, and digital signatures.
With this API, you can also create, search, and verify electronic signatures for popular document formats, and customize your signing options to fit your needs.
This on-premise .NET API lets your app end-users sign the electronic documents from a wide range of file formats. Supports several types of e-signing methods.
GroupDocs.Signature for .NET does not require any external software or third-party tool to be installed. GroupDocs.Signature for .NET supports any 32-bit or 64-bit operating system where .NET or Mono framework is installed. The other details are as follows:
Microsoft Windows: Microsoft Windows Desktop (x86, x64) (XP & up), Microsoft Windows Server (x86, x64) (2000 & up), Windows Azure Mac OS: Mac OS X Linux: Linux (Ubuntu, OpenSUSE, CentOS and others) Development Environments: Microsoft Visual Studio (2010 & up), Xamarin.Android, Xamarin.IOS, Xamarin.Mac, MonoDevelop 2.4 and later. Supported Frameworks: GroupDocs.Conversion for .NET supports .NET and Mono frameworks.
Are you ready to give GroupDocs.Signature for .NET a try? Simply execute Install-Package GroupDocs.Signature from Package Manager Console in Visual Studio to fetch & reference GroupDocs.Signature assembly in your project. If you already have GroupDocs.Signature for .Net and want to upgrade it, please execute Update-Package GroupDocs.Signature to get the latest version.
Please check the GitHub Repository for other common usage scenarios.
The example below shows how to sign a PDF document with a digital e-signature using C# language. We can sign any other supported document format in the same way
using (Signature signature = new Signature("sample.pdf"))
{
// initialize digital option with certificate file path
DigitalSignOptions options = new DigitalSignOptions("certificate.pfx")
{
// set signature position
Left = 100,
Top = 100,
Password = "1234567890"
};
signature.Sign("signed.pdf", options);
}
The code snippet below demonstrates how to sign a PDF document with the QR code signature
using (Signature signature = new Signature("sample.pdf"))
{
// create QRCode option with predefined QRCode text
QrCodeSignOptions options = new QrCodeSignOptions("JohnSmith")
{
// setup QRCode encoding type
EncodeType = QrCodeTypes.QR,
// set signature position
Left = 100,
Top = 100
};
signature.Sign("signed.pdf", options);
}
This example shows how to search for Digital signature in the document and analyze digital signature certificate
using (Signature signature = new Signature("spreadsheet.xlsx"))
{
// search for signatures in document
List<DigitalSignature> signatures = signature.Search<DigitalSignature>(SignatureType.Digital);
Console.WriteLine("\nSource document contains following signatures.");
foreach (var digitalSignature in signatures)
{
Console.WriteLine("Digital signature found from {0} with validation flag {1}. Certificate SN {2}",
digitalSignature.SignTime, digitalSignature.IsValid, digitalSignature.Certificate?.SerialNumber);
}
}
This example shows how to delete Digital signature that was found using Search method
using (Signature signature = new Signature("signed.pdf"))
{
List<DigitalSignature> signatures =
signature.Search<DigitalSignature>(SignatureType.Digital);
if (signatures.Count > 0)
{
DigitalSignature digitalSignature = signatures[0];
bool result = signature.Delete(digitalSignature);
if (result)
{
Console.WriteLine(
$"Digital signature #{digitalSignature.Thumbprint} from " +
$"{digitalSignature.SignTime.ToShortDateString()} was deleted."
);
}
else
{
Console.WriteLine(
$"Signature was not deleted from the document! " +
$"Signature# {digitalSignature.Thumbprint} was not found!"
);
}
}
}
