How to redact PDF using C# and VB.NET
Redaction is the process of removing sensitive or unwanted content from a document. Syncfusion Essential PDF is a .NET PDF library used to create, read, and edit PDF documents. Using this library, you can redact text and images from the PDF document.
Steps to redact 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 the Program.cs file.
C#
using Syncfusion.Pdf; using Syncfusion.Pdf.Parsing; using Syncfusion.Pdf.Redaction; using System.Drawing;
VB.NET
Imports Syncfusion.Pdf Imports Syncfusion.Pdf.Parsing Imports Syncfusion.Pdf.Redaction Imports System.Drawing
- Use the following code snippet to redact PDF document.
C#
//Load an existing PDF document
PdfLoadedDocument document = new PdfLoadedDocument("Input.pdf");
//Get first page from the document
PdfLoadedPage page = document.Pages[0] as PdfLoadedPage;
//Create PDF redaction for the page
PdfRedaction redaction = new PdfRedaction(new RectangleF(475, 158, 60, 17), System.Drawing.Color.Black);
//Adds redaction to the loaded page
page.Redactions.Add(redaction);
//Save and close the PDF document
document.Save("RedactedPDF.pdf");
document.Close(true);
//This will open the PDF file so, the result will be seen in default PDF viewer
System.Diagnostics.Process.Start("RedactedPDF.pdf");
VB.NET
'Load an existing PDF document
Dim document As PdfLoadedDocument = New PdfLoadedDocument("Input.pdf")
'Get first page from the document
Dim page As PdfLoadedPage = TryCast(document.Pages(0), PdfLoadedPage)
'Create PDF redaction for the page
Dim redaction As PdfRedaction = New PdfRedaction(New RectangleF(475, 158, 60, 17), System.Drawing.Color.Black)
'Adds redaction to the loaded page
page.Redactions.Add(redaction)
'Save and close the PDF document
document.Save("RedactedPDF.pdf")
document.Close(True)
'This will open the PDF file so, the result will be seen in default PDF viewer
System.Diagnostics.Process.Start("RedactedPDF.pdf")
A complete working sample can be downloaded from RedactionSample.zip.
By executing the program, you will get the PDF document as follows.
Take a moment to peruse the documentation, where you can find other options like display text, image, and pattern on the redacted area, fill color on the redacted area. Also, redact the PDF without drawing the fill color, appearance, and features like encrypt and decrypt PDF document and digitally sign a PDF file with code examples.
Refer here to explore the rich set of Syncfusion Essential PDF features.
An online sample link to redact PDF document.
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.
