Are you tired of paying for Individual Agents – v1

Many professional sectors and industries are using PDF file format to view, print, and share all kinds of information. Imagine a PDF document that has information with legal value. Such a document may contain important information about rights and obligations, in which case you need to ensure its authenticity and integrity. The solution is adding a digital signature in your PDF document. The Syncfusion PDF Library provides support to create and validate PDF digital signatures using C# or VB.NET.

In this blog, I am going to show you how to create and validate a PDF digital signature using the Syncfusion PDF Library that will help you and your organization to achieve the following benefits:

1.Introduction

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I. Loreum Ipsum dolor

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Sample line include :

• Digitally sign a PDF that is legally valid across the world.
• Add extra security to your signatures.
• Bulk sign.
• Eliminate physical signing and improve time management.
• Improve cost effectiveness.

• Eliminate physical signing and improve time management.
• Improve cost effectiveness.

2.Rules and Regulations

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I. Loreum Ipsum dolor

Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nunc vulputate libero et velit interdum, ac aliquet odio mattis. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos.

Maintain the Rules as follows :

1. Digitally sign a PDF that is legally valid across the world.
2. Add extra security to your signatures.
3. Bulk sign.
4. Eliminate physical signing and improve time management.
5. Improve cost effectiveness.
6. Add a timestamp to a digital signature
7. Digitally sign a PDF document with long-term validation (LTV)

Example 2:

Table

Code

using Syncfusion.Pdf.Parsing;
using Syncfusion.Pdf.Security;
class Program
{
    static void Main(string[] args)
    {
        //Load existing PDF document.
        PdfLoadedDocument document = new PdfLoadedDocument("PDF_Succinctly.pdf");
        //Load digital ID with password.
        PdfCertificate certificate = new PdfCertificate(@"DigitalSignatureTest.pfx", "DigitalPass123");
        //Create a signature with loaded digital ID.
        PdfSignature signature = new PdfSignature(document, document.Pages[0], certificate, "DigitalSignature");
        //Save the PDF document.
        document.Save("SignedDocument.pdf");
        //Close the document.
        document.Close(true);
    }
}

3.Conclusion

By default, the Syncfusion PDF Library generates digital signatures with CMS (part 2 of the PAdES) standard and SHA 256 hashing algorithm.
You can change the digital signature standard to CAdES (part 3 of the PAdES) using the property CryptographicStandard available in the class PdfSignatureSettings. It also has the property DigestAlgorithm to change the hashing algorithm.
The following code example shows how to add a digital signature with CAdES standard with a different hashing algorithm.