TX Text Control is able to digitally sign Adobe PDF and PDF/A documents with X.509 certificates. The certificate can be assigned in the SaveSettings TX Text Control .NET for Windows Forms
TXTextControl Namespace
SaveSettings Class
The SaveSettings class provides properties for advanced settings and information during save operations.
class when saving document.

Signing With Certificate Files

TX Text Control can be used to sign PDF documents with a X509Certificate2 that is created from a PFX certificate file. This is typically used for automated processes where a PFX file can be stored on a server and no user interaction is required. The following code shows how to sign a PDF document with a PFX file:

Loading...

Signing With Smart Cards

By accepting a certificate provided by the Windows certificate store, you can sign documents with smart cards, PIV cards or USBs such as YubiKey.

The X509Certificate2UI class provides a UI to select and view X.509 certificates. In the following code, the SelectFromCollection method is used to open a dialog for selecting the certificate. All registered certificates including smart cards are listed in the dialog box.

Loading...

Certificate

After the document has been created and is opened in Acrobat Reader, the valid signatures are shown in the Signatures sidebar:

PDF Acrobat Reader