# How to Sign Signature Fields with Custom Signer Information and Time Stamps in ASP.NET Core C# > This article shows how to sign signature fields in a PDF document with custom signer information and timestamps using the TX Text Control .NET Server component in ASP.NET Core C#. The signature is created using a PFX certificate file. - **Author:** Bjoern Meyer - **Published:** 2024-06-21 - **Modified:** 2026-07-17 - **Description:** This article shows how to sign signature fields in a PDF document with custom signer information and timestamps using the TX Text Control .NET Server component in ASP.NET Core C#. The signature is created using a PFX certificate file. - **3 min read** (484 words) - **Tags:** - ASP.NET - ASP.NET Core - Certificate - Electronic Signature - PFX - **Web URL:** https://www.textcontrol.com/blog/2024/06/21/how-to-sign-signature-fields-with-custom-signer-information-and-time-stamps-in-asp-net-core-c-sharp/ - **LLMs URL:** https://www.textcontrol.com/blog/2024/06/21/how-to-sign-signature-fields-with-custom-signer-information-and-time-stamps-in-asp-net-core-c-sharp/llms.txt - **LLMs-Full URL:** https://www.textcontrol.com/blog/2024/06/21/how-to-sign-signature-fields-with-custom-signer-information-and-time-stamps-in-asp-net-core-c-sharp/llms-full.txt --- TX Text Control provides a powerful API to sign PDF documents with signature fields and digital signatures. This article shows how to sign a PDF document with a digital signature using the TX Text Control API and to set custom signer information. ### Pre-Populated Signer Information Signer information, such as the reason for signing and the signer's address, can be added at the design time of the document or template. This information is stored in the internal TX Text Control document format and can be used to pre-fill the signature fields. The following screenshots show a signature field and the ribbon bar with the pre-populated information: ![Signer Information and TX Text Control](https://s1-www.textcontrol.com/assets/dist/blog/2024/06/21/a/assets/signer1.webp "Signer Information and TX Text Control") When signing the document with a digital signature, the pre-populated information is used automatically. ### Custom Signer Information When signing a document with a digital signature, the signer information can be set programmatically using the SignerData property. This property is an instance of the SignerData class that provides the following properties: | Property | Description | |---|---| | `Reason` | Gets or sets the reason for signing the document. | | `Address` | Gets or sets the location of the signer. | | `ContactInfo` | Gets or sets the contact information of the signer. | | `Name` | Gets or sets the name of the signer. | | `Title` | Gets or sets the title of the signer. | The following code snippet shows how to set the signer information for a signature field: ``` using System.Security.Cryptography.X509Certificates; using TXTextControl; using (TXTextControl.ServerTextControl tx = new TXTextControl.ServerTextControl()) { tx.Create(); tx.Load("signature.tx", TXTextControl.StreamType.InternalUnicodeFormat); // create a certificate X509Certificate2 cert = new X509Certificate2("textcontrolself.pfx", "123"); // create a list of digital signatures var digitalSignatures = new List(); foreach (SignatureField signatureField in tx.SignatureFields) { signatureField.SignerData = new SignerData( "John Doe", "CEO", "11 Main Street, New York, NY 10001, USA", "john@doe.com", "Contract signature"); // time stamp server var timeStampServer = "http://timestamp.digicert.com"; // create a digital signature object DigitalSignature digitalSignature = new DigitalSignature(cert, timeStampServer, signatureField.Name); // add the digital signature to the list digitalSignatures.Add(digitalSignature); } // create save settings SaveSettings saveSettings = new SaveSettings() { CreatorApplication = "Your Application", SignatureFields = digitalSignatures.ToArray() }; // save the document as PDF tx.Save("results_signed.pdf", StreamType.AdobePDFA, saveSettings); } ``` Additionally, the time server is added to the digital signature. The *timeServerURL* parameter is set to the URL of the time server. When the document is signed, the signature field is updated with the custom signer information: ![Custom Signer Information](https://s1-www.textcontrol.com/assets/dist/blog/2024/06/21/a/assets/signer2.webp "Custom Signer Information") When the document is opened in Adobe Acrobat Reader, the custom signer information is displayed in the signature properties. ### Conclusion TX Text Control provides a powerful API to sign PDF documents with signature fields and digital signatures. The signer information can be pre-populated at the design time of the document or set programmatically using the SignerData property. --- ## About Bjoern Meyer As CEO, Bjoern is the visionary behind our strategic direction and business development, bridging the gap between our customers and engineering teams. His deep passion for coding and web technologies drives the creation of innovative products. If you're at a tech conference, be sure to stop by our booth - you'll most likely meet Bjoern in person. With an advanced graduate degree (Dipl. Inf.) in Computer Science, specializing in AI, from the University of Bremen, Bjoern brings significant expertise to his role. In his spare time, Bjoern enjoys running, paragliding, mountain biking, and playing the piano. - [LinkedIn](https://www.linkedin.com/in/bjoernmeyer/) - [X](https://x.com/txbjoern) - [GitHub](https://github.com/bjoerntx) --- ## Related Posts - [How to Sign PDF Documents with PFX Certificates in .NET C# on Linux](https://www.textcontrol.com/blog/2025/03/19/how-to-sign-pdf-documents-with-pfx-certificates-in-net-c-sharp-on-linux/llms.txt) - [Secure by Design: Dynamic Watermarking for Enterprise Documents in C# .NET](https://www.textcontrol.com/blog/2026/02/06/secure-by-design-dynamic-watermarking-for-enterprise-documents-in-csharp-dotnet/llms.txt) - [E-Sign Comes to Blazor: Document Viewer 33.0.1 Released](https://www.textcontrol.com/blog/2025/04/24/e-sign-comes-to-blazor-document-viewer-33-0-1-released/llms.txt) - [Adoption of Electronic vs. Paper Signatures in 2025](https://www.textcontrol.com/blog/2025/04/15/adoption-of-electronic-vs-paper-signatures-in-2025/llms.txt) - [Sign Documents with a Self-Signed Digital ID From Adobe Acrobat Reader in .NET C#](https://www.textcontrol.com/blog/2024/08/12/sign-documents-with-a-self-signed-digital-id-from-adobe-acrobat-reader-in-net-c-sharp/llms.txt) - [Transforming Financial Documents into Smart and Secure Forms in ASP.NET Core C#](https://www.textcontrol.com/blog/2024/05/01/transforming-financial-documents-into-smart-and-secure-forms-in-asp-net-core-c-sharp/llms.txt) - [Customize Signature Fields with Dynamically Created SVG Images](https://www.textcontrol.com/blog/2023/01/13/customize-signature-fields-with-dynamically-created-svg-images/llms.txt) - [Whitepaper: Integrate On-Premise Electronic Signature Processes into Web Applications](https://www.textcontrol.com/blog/2022/03/07/whitepaper-integrate-onpremise-electronic-signature-processes-into-web-applications/llms.txt) - [Document Viewer: Uploading Signatures](https://www.textcontrol.com/blog/2022/02/24/document-viewer-uploading-signatures/llms.txt) - [Handling Signature Requests in ASP.NET Core](https://www.textcontrol.com/blog/2022/02/04/handling-signature-requests-in-aspnet-core/llms.txt) - [Electronic Signatures: Document Signing by Routing Requests to Custom Endpoints](https://www.textcontrol.com/blog/2022/02/03/electronic-signatures-custom-signing-processes/llms.txt) - [Storing Documents on the Blockchain](https://www.textcontrol.com/blog/2022/01/21/storing-documents-on-the-blockchain/llms.txt) - [DocumentViewer Mobile-Friendly View Released](https://www.textcontrol.com/blog/2022/01/20/document-viewer-mobile-friendly-view-released/llms.txt)