Adding Digital Signature

How to Add Visible Digital Signature to PDF in C#

The following steps and sample code illustrate adding a visible digital signature to a PDF using DynamicPDF Core Suite.

Steps for Adding a Visible Digital Signature to a PDF Document

1. Create a Document object.
2. Create a Page object.
3. Create a Signature object and set its properties in the constructor.
4. Add the Signature object to the Page object.
5. Add the Page object to the Document object.
6. Create a Certificate object and set its properties.
7. Sign the document with the Visible Digital Signature field name.
8. Save the PDF document.

Sample Code - C#

Document document = new Document();
Page page = new Page(PageSize.Letter);
            
Signature signature = new Signature("SigField", 10, 10, 250, 100);
page.Elements.Add(signature);
document.Pages.Add(page);
Certificate certificate = new Certificate(@"JohnDoe.pfx", "password");

document.Sign("SigField", certificate);
            
document.Draw(@"Output.pdf");        

How to Add Invisible Digital Signature to PDF in C#

The following steps and sample code add an invisible Digital Signature to a PDF document using DynamicPDF Core Suite.

Steps for Adding an Invisible Digital Signature to a PDF Document

1. Create a Document object.
2. Create a Page object.
3. Add the Page instance to the Document instance.
4. Create a Certificate object and set its properties.
5. Sign the document with a non-existent field name and the Certificate.
6. Save the PDF document.

Sample Code - C#

Document document = new Document();
Page page = new Page();

document.Pages.Add(page);
Certificate certificate = new Certificate(@"JohnDoe.pfx", "password");

// Field name should not match any field names in the document 
document.Sign("NonExistingField", certificate);
document.Draw(@"Output.pdf");         

GitHub Project

Clone or view the example project at GitHub. This example code is contained in the Examples/DigitalSignatureExample.cs file.

Getting Started

NuGet Package

DynamicPDF Generator is available on NuGet and is part of the ceTe.DynamicPDF.CoreSuite.NET package. The easiest way to install the package is through the Visual Studio Package Manager. You can also download the package directly from NuGet.

DynamicPDF Core Suite Information

More information on DynamicPDF Core Suite can be found on its website.

• DynamicPDF Core Suite for .NET

Available on Other Platforms

DynamicPDF Core Suite is also available for the Java and COM/ActiveX platforms. Refer to the respective product pages for more details.

• Java - DynamicPDF Generator for Java
• COM/ActiveX - DynamicPDF Generator for COM/ActiveX