Redact PDF, Word, Excel, PowerPoint, and image files in .NET

Use the exact phrase to redact text in .NET

If you are looking to replace text containing important personal details from a file with custom text using the exact phrase, please use the C# code given below. This code will replace the name 'John Doe' with the specified text thus redacting the name of the person from the document:

using (Redactor redactor = new Redactor(@"sample.docx"))
{
  redactor.Apply(new ExactPhraseRedaction("John Doe", new ReplacementOptions("[personal]")));
  redactor.Save();
} 

For applying a rectangular black-colored box over the redacted text instead of a replacement string, please use the following code snippet:

using (Redactor redactor = new Redactor(@"sample.docx"))
{
  redactor.Apply(new ExactPhraseRedaction("John Doe", new ReplacementOptions(System.Drawing.Color.Black)));
  redactor.Save();
}
    

Using a regular expression for redacting text

You can also use a regular expression for redacting. The below-given C# code will redact text which matches the regular expression sequence of 'two digits, space, two digits, space again and six digits' (example: 12 34 567890) while also inserting a blue-colored rectangular box in place of the redacted text:

using (Redactor redactor = new Redactor(@"sample.docx"))
{
  redactor.Apply(new RegexRedaction("\\d{2}\\s*\\d{2}[^\\d]*\\d{6}", new ReplacementOptions(System.Drawing.Color.Blue)));
  redactor.Save();
}

Build C#, .NET redaction apps to obscure and delete annotation contents

Please utilize the following C# code to redact the contents of annotations from your .NET documents of PDF, Word, Excel, PowerPoint, RTF, and many other formats:

using (Redactor redactor = new Redactor(@"C:\sample.pdf"))
{
//Redacting all occurrences of ‘John’ from document annotations
redactor.Apply(new AnnotationRedaction("(?im:john)", "[redacted]"));
   redactor.Save()
}    

Remove annotations programmatically from your multi-format .NET files

Just like redacting what’s contained within the annotations, you can completely remove the annotations if needed. Please use the code given below to achieve this:

using (Redactor redactor = new Redactor(@"C:\sample.docx"))
{
   //Deleting comments or annotations containing ‘use’, ‘show’, ‘describe’
   redactor.Apply(new DeleteAnnotationRedaction("(?im:(use|show|describe))"));

   redactor.Save()
} 

Redact a specified area inside an image file

To redact a certain area in an image, please use the C# code shown below. While we are using a JPG image in this sample code, you may use any of the other supported image formats such as PNG, GIF, TIFF, or BMP:

    using (Redactor redactor = new Redactor("D:\\sample.jpg"))
    {
       System.Drawing.Point samplePoint = new System.Drawing.Point(516, 311);
       System.Drawing.Size sampleSize = new System.Drawing.Size(170, 35);
       RedactorChangeLog result = redactor.Apply(new ImageAreaRedaction(samplePoint,
                    new RegionReplacementOptions(System.Drawing.Color.Blue, sampleSize)));
       if (result.Status != RedactionStatus.Failed)
       {
          redactor.Save();
       };
    }     

Apply embedded image redaction in .NET

Along with the usual image redaction, you can also redact images embedded in a document using GroupDocs.Redaction for .NET. To redact images embedded with a Microsoft Word file, please use the following code snippet:

    using (Redactor redactor = new Redactor("D:\\sample.docx"))
    {
       System.Drawing.Point samplePoint = new System.Drawing.Point(516, 311);
       System.Drawing.Size sampleSize = new System.Drawing.Size(170, 35);
       RedactorChangeLog result = redactor.Apply(new ImageAreaRedaction(samplePoint,
                    new RegionReplacementOptions(System.Drawing.Color.Blue, sampleSize)));
       if (result.Status != RedactionStatus.Failed)
       {
          redactor.Save();
       };
    }     

Save the redacted document to its original format

This sample code shows how to save a Word document in its original format after redacting it:

    using (Redactor redactor = new Redactor(@"sample.docx"))
{
    // Applying redactions
    redactor.Apply(new ExactPhraseRedaction("John Doe", new ReplacementOptions("[personal]")));
    // Saving to original format by adding the date as a suffix
    redactor.Save(new SaveOptions() { AddSuffix = true, RasterizeToPDF = false, RedactedFileSuffix = DateTime.Now.ToShortDateString() });
}
    

Saving the redacted document as a rasterized PDF

You may save the file after redaction as a rasterized PDF, please use the following code to do this:

    using (Redactor redactor = new Redactor(@"sample.docx"))
{
    // Applying redactions
    redactor.Apply(new ExactPhraseRedaction("John Doe", new ReplacementOptions("[personal]")));
    // Saving the redacted file as a rasterized PDF
    redactor.Save(new SaveOptions() { AddSuffix = false, RasterizeToPDF = true });
}