New to Telerik Document Processing? Start a free 30-day trial
SignatureField class
Updated on May 11, 2026
This article describes the following topics:
Overview
This class corresponds to FormFieldType.Signature enum value and represents a placeholder which preserves the digital signature information.
To use the signing functionality in PdfProcessing for .NET Standard/.NET Core, you must add a reference to the System.Security.Cryptography.Pkcs NuGet package, version 9.0.9 or newer (This functionality is available since R1 2022 SP1).
Properties
SignatureField provides the following properties:
| Property | Description |
|---|---|
Signature | Gets or sets the Signature value. Setting this property will sign the document during export. Signing with multiple signatures is not currently supported. To validate a signature, use the Validate() and TryValidate() methods. Validation requires that the source stream be open and is performed against the document state at import time. See Digital Signature for more details. |
Widgets | The collection of Widget annotations representing the field on the PDF pages. Widgets can be added using AddWidget() and removed using Remove(). Implements IEnumerable. |
Example 1: Create a SignatureField and add it to a page
C#
RadFixedDocument document = new RadFixedDocument();
X509Certificate2 certificate = new X509Certificate2("JohnDoe.pfx", "johndoe");
SignatureField signatureField = new SignatureField("SampleSignature");
signatureField.Signature = new Signature(certificate); // The Signature property fo SignatureField is not available in PdfProcessing for .NET Standard.
SignatureWidget widget = signatureField.Widgets.AddWidget();
widget.Rect = new Rect(200, 600, 100, 100);
widget.Border = new AnnotationBorder(5, AnnotationBorderStyle.Solid, null);
//Create a Form object to define the appearance you would like for the signature field.
Telerik.Windows.Documents.Fixed.Model.Objects.Form form = new Telerik.Windows.Documents.Fixed.Model.Objects.Form();
form.FormSource = new FormSource();
form.FormSource.Size = new Size(120, 120);
FixedContentEditor formEditor = new FixedContentEditor(form.FormSource);
formEditor.DrawCircle(new Point(50, 50), 20);
formEditor.DrawText("Sample Signature");
//Add the FormSource object to the widget of the field.
widget.Content.NormalContentSource = form.FormSource;
RadFixedPage page = document.Pages.Last();
page.Annotations.Add(widget);
document.AcroForm.FormFields.Add(signatureField);