> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/xamarin/get-started/samples/pdfredacttest.md).
# PDFRedact
Sample C# code for using Apryse SDK to remove potentially sensitive content within PDF documents. Using 'pdftron.PDF.Redactor' makes sure that if a portion of an image, text, or vector graphics is con
Sample C# code for using Apryse SDK to remove potentially sensitive content within PDF documents. Using 'pdftron.PDF.Redactor' makes sure that if a portion of an image, text, or vector graphics is contained in a redaction region, that portion is destroyed and is not simply hidden with clipping or image masks. Learn more about our [Xamarin SDK](/core/get-started/frameworks/dotnet.md).
{% tabs %}
{% tab title="C#" %}
{% code lineNumbers="true" %}
```csharp
//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2021 by PDFTron Systems Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------
using System;
using System.IO;
using System.Collections;
using pdftron;
using pdftron.Common;
using pdftron.Filters;
using pdftron.SDF;
using pdftron.PDF;
using NUnit.Framework;
namespace MiscellaneousSamples
{
// PDF Redactor is a separately licensable Add-on that offers options to remove
// (not just covering or obscuring) content within a region of PDF.
// With printed pages, redaction involves blacking-out or cutting-out areas of
// the printed page. With electronic documents that use formats such as PDF,
// redaction typically involves removing sensitive content within documents for
// safe distribution to courts, patent and government institutions, the media,
// customers, vendors or any other audience with restricted access to the content.
//
// The redaction process in PDFNet consists of two steps:
//
// a) Content identification: A user applies redact annotations that specify the
// pieces or regions of content that should be removed. The content for redaction
// can be identified either interactively (e.g. using 'pdftron.PDF.PDFViewCtrl'
// as shown in PDFView sample) or programmatically (e.g. using 'pdftron.PDF.TextSearch'
// or 'pdftron.PDF.TextExtractor'). Up until the next step is performed, the user
// can see, move and redefine these annotations.
// b) Content removal: Using 'pdftron.PDF.Redactor.Redact()' the user instructs
// PDFNet to apply the redact regions, after which the content in the area specified
// by the redact annotations is removed. The redaction function includes number of
// options to control the style of the redaction overlay (including color, text,
// font, border, transparency, etc.).
//
// PDFTron Redactor makes sure that if a portion of an image, text, or vector graphics
// is contained in a redaction region, that portion of the image or path data is
// destroyed and is not simply hidden with clipping or image masks. PDFNet API can also
// be used to review and remove metadata and other content that can exist in a PDF
// document, including XML Forms Architecture (XFA) content and Extensible Metadata
// Platform (XMP) content.
[TestFixture]
public class PDFRedactTest
{
static void Redact(string input, string output, ArrayList rarr, Redactor.Appearance app)
{
using (PDFDoc doc = new PDFDoc(input))
{
doc.InitSecurityHandler();
Redactor.Redact(doc, rarr, app, false, true);
doc.Save(output, SDFDoc.SaveOptions.e_linearized);
}
}
///
/// The following sample illustrates how to redact a PDF document using 'pdftron.PDF.Redactor'.
///
[Test]
public static void Sample()
{
const string input_path = "TestFiles/";
try
{
ArrayList rarr = new ArrayList();
rarr.Add(new Redactor.Redaction(1, new Rect(100, 100, 550, 600), false, "Top Secret"));
rarr.Add(new Redactor.Redaction(2, new Rect(30, 30, 450, 450), true, "Negative Redaction"));
rarr.Add(new Redactor.Redaction(2, new Rect(0, 0, 100, 100), false, "Positive"));
rarr.Add(new Redactor.Redaction(2, new Rect(100, 100, 200, 200), false, "Positive"));
rarr.Add(new Redactor.Redaction(2, new Rect(300, 300, 400, 400), false, ""));
rarr.Add(new Redactor.Redaction(2, new Rect(500, 500, 600, 600), false, ""));
rarr.Add(new Redactor.Redaction(3, new Rect(0, 0, 700, 20), false, ""));
Redactor.Appearance app = new Redactor.Appearance();
app.RedactionOverlay = true;
app.Border = false;
app.ShowRedactedContentRegions = true;
Redact(Utils.GetAssetTempFile(input_path + "newsletter.pdf"), Utils.CreateExternalFile("redacted.pdf"), rarr, app);
Console.WriteLine("Done...");
}
catch (PDFNetException e)
{
Console.WriteLine(e.Message);
Assert.True(false);
}
}
}
}
```
{% endcode %}
{% endtab %}
{% endtabs %}
---
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