How to hide the signature field in a PDF using C# and VB.NET?
Syncfusion Essential PDF is a .NET PDF library used to create, read, and edit PDF documents. Using this library, you can hide the signature field in a PDF using C# and VB.NET.
Steps to hide the signature field in a PDF programmatically:
- Create a new C# console application project.
- Install the Syncfusion.Pdf.WinForms NuGet package as reference to your .NET Framework application from NuGet.org.
- Include the following namespaces in Program.cs file.
C#
using Syncfusion.Pdf; using Syncfusion.Pdf.Interactive; using Syncfusion.Pdf.Parsing; using Syncfusion.Pdf.Security;
VB.NET
Imports Syncfusion.Pdf Imports Syncfusion.Pdf.Parsing Imports Syncfusion.Pdf.Interactive Imports Syncfusion.Pdf.Security
- Use the following code snippet to hide the signature field in a PDF document.
C#
//Loads a PDF document
PdfLoadedDocument loadedDocument = new PdfLoadedDocument("Form.pdf");
//Gets the first page of the document
PdfLoadedPage page = loadedDocument.Pages[0] as PdfLoadedPage;
//Gets the first signature field of the PDF document
PdfLoadedSignatureField signatureField = loadedDocument.Form.Fields[0] as PdfLoadedSignatureField;
//Hide the visibility of the signature field
signatureField.Visibility = PdfFormFieldVisibility.Hidden;
//Creates a certificate
PdfCertificate certificate = new PdfCertificate(@"PDF.pfx", "syncfusion");
signatureField.Signature = new PdfSignature(loadedDocument, page, certificate, "Signature", signatureField);
//Saves the document
loadedDocument.Save("Signature.pdf");
//Closes the document
loadedDocument.Close(true);
//This will open the PDF file so, the result will be seen in default PDF viewer
Process.Start("Signature.pdf");
VB.NET
'Loads a PDF document
Dim loadedDocument As PdfLoadedDocument = New PdfLoadedDocument("Form.pdf")
'Gets the first page of the document
Dim page As PdfLoadedPage = TryCast(loadedDocument.Pages(0), PdfLoadedPage)
'Gets the first signature field of the PDF document
Dim signatureField As PdfLoadedSignatureField = TryCast(loadedDocument.Form.Fields(0), PdfLoadedSignatureField)
'Hide the visibility of the signature field
signatureField.Visibility = PdfFormFieldVisibility.Hidden
'Creates a certificate
Dim certificate As PdfCertificate = New PdfCertificate("PDF.pfx", "syncfusion")
signatureField.Signature = New PdfSignature(loadedDocument, page, certificate, "Signature", signatureField)
'Saves the document
loadedDocument.Save("Signature.pdf")
'Closes the document
loadedDocument.Close(True)
'This will open the PDF file so, the result will be seen in default PDF Viewer
Process.Start("Signature.pdf")
A complete working sample can be downloaded from PDFFormSample.zip.
Take a moment to peruse the documentation, where you can find other options like add form fields to PDF, modifying existing form fields, filling form fields, removing editing capability, removing form fields, importing FDF file to PDF, export PDF file to FDF, adding actions to form fields, and features like Digital Signature and XFA Form code examples.
Refer here to learn more about PDF forms in Syncfusion .NET PDF library.
Starting with v16.2.0.x, if you reference Syncfusion assemblies from trial setup or from the NuGet feed, include a license key in your projects. Refer to link to learn about generating and registering Syncfusion license key in your application to use the components without trail message.
Conclusion
I hope you enjoyed learning about how to hide the signature field in a PDF using C# and VB.NET.
You can refer to our WinForms PDF’s feature tour page to know about its other groundbreaking feature representations. You can also explore our WinForms PDF documentation to understand how to present and manipulate data.
For current customers, you can check out our WinForms from the License and Downloads page. If you are new to Syncfusion, you can try our 30-day free trial to check out our WinForms PDF and other WinForms components.
If you have any queries or require clarifications, please let us know in comments below. You can also contact us through our support forums, Direct-Trac, or feedback portal. We are always happy to assist you!
