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Features
SIGN & SECURE

Sign and Secure PDFs

Secure and guarantee PDF authenticity with modern encryption, permissions, and signatures in a few lines of code.

IRONPDFFEATURES

Ensure Your Document Authenticity
Enhance with Seamless PDF Form Management
Assure the Safety of Your Documentation

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Ensure Your Document Authenticity

1

Digital Signature

Digitally sign your PDFs to authenticate them and provide proof of authorship or approval. This feature is essential for legal or official documentation.

Learn how to:sign your PDFs 
using IronPdf;
using IronPdf.Signing;
// Cryptographically sign an existing PDF in 1 line of code!
new IronPdf.Signing.PdfSignature("Iron.p12", "123456").SignPdfFile("any.pdf");
C#
2

Edit & Sign Revision History

Maintain and edit the revision history of your PDF documents. Track changes, approvals, and signatures over time for better document management.

Learn how to:edit and revision PDFs 
using IronPdf;
using IronPdf.Rendering;
// Import PDF and enable TrackChanges
PdfDocument pdf = PdfDocument.FromFile("annual_census.pdf", TrackChanges: ChangeTrackingModes.EnableChangeTracking);
// ... Various edits ...
pdf.SignWithFile("/assets/IronSignature.p12", "password", null, IronPdf.Signing.SignaturePermissions.AdditionalSignaturesAndFormFillingAllowed);
PdfDocument pdfWithRevision = pdf.SaveAsRevision();
pdfWithRevision.SaveAs("annual_census_2.pdf");
C#
3

Edit PDF Metadata

Edit the metadata of your PDF files, such as author, title, and subject, to improve document organization and searchability.

Learn how to:edit Metadata 
using IronPdf;
using System;

ChromePdfRenderer renderer = new ChromePdfRenderer();
PdfDocument pdf = renderer.RenderHtmlAsPdf("<h1>Metadata</h1>");
// Access the MetaData class and set the pre-defined metadata properties.
pdf.MetaData.Author = "Iron Software";
pdf.MetaData.CreationDate = DateTime.Today;
pdf.MetaData.Creator = "IronPDF";
pdf.SaveAs("pdf-with-metadata.pdf");
C#

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Enhance with Seamless PDF Form Management

1

Create PDF Forms

Create interactive PDF forms with fillable fields, checkboxes, radio buttons, and more. Ideal for gathering information or creating surveys.

Learn how to:create PDF forms 
using IronPdf;

// Input and Text Area forms HTML
string FormHtml = @"
<html>
    <body>
        <h2>Editable PDF Form</h2>
        <form>
            First name: <br> <input type='text' name='firstname' value=''> <br>
            Last name: <br> <input type='text' name='lastname' value=''> <br>
            Address: <br> <textarea name='address' rows='4' cols='50'></textarea>
        </form>
    </body>
</html>
";

// Instantiate Renderer
ChromePdfRenderer Renderer = new ChromePdfRenderer();
Renderer.RenderingOptions.CreatePdfFormsFromHtml = true;
Renderer.RenderHtmlAsPdf(FormHtml).SaveAs("textAreaAndInputForm.pdf");
C#
2

Fill & Edit Existing Forms

Fill out and edit existing PDF forms with ease. Modify form fields, update content, and save changes for seamless document management.

Learn how to:fill and edit forms 
using IronPdf;

PdfDocument pdf = PdfDocument.FromFile("textAreaAndInputForm.pdf");

// Set text input form values
pdf.Form.FindFormField("firstname").Value = "John";
pdf.Form.FindFormField("lastname").Value = "Smith";

// Set text area form values
pdf.Form.FindFormField("address").Value = "Iron Software LLC\r\n205 N. Michigan Ave.";

pdf.SaveAs("textAreaAndInputFormEdited.pdf");
C#
3

Flatten Form Fields

Flatten form fields to lock in entered data and prevent further edits, ensuring the integrity of the form content.

Learn how to:flatten form fields 
using IronPdf;

// Select the desired PDF File
PdfDocument pdf = PdfDocument.FromFile("textAreaAndInputFormEdited.pdf");

// Flatten the pdf
pdf.Flatten();

// Save as a new file
pdf.SaveAs("after_flatten.pdf");
C#

Icon Main related to Sign and Secure PDFs
Assure the Safety of Your Documentation

1

Sanitize PDFs

Sanitize your PDFs by removing hidden metadata, sensitive content, and comments to protect your document's confidentiality and security.

Learn how to:sanitize PDFs 
using IronPdf;

// Import PDF document
PdfDocument pdf = PdfDocument.FromFile("sample.pdf");

// Sanitize with Bitmap
PdfDocument sanitizeWithBitmap = Cleaner.SanitizeWithBitmap(pdf);

// Sanitize with SVG
PdfDocument sanitizeWithSvg = Cleaner.SanitizeWithSvg(pdf);

// Export PDFs
sanitizeWithBitmap.SaveAs("sanitizeWithBitmap.pdf");
sanitizeWithSvg.SaveAs("sanitizeWithSvg.pdf");
C#
2

Set Password & Permissions

Set passwords and permissions on your PDFs to control access, prevent unauthorized editing, and protect sensitive information.

Learn how to:set PDFs permissions 
using IronPdf;

ChromePdfRenderer renderer = new ChromePdfRenderer();

PdfDocument pdf = renderer.RenderHtmlAsPdf("<h1>Secret Information:</h1> Hello World");

// Password to edit the pdf
pdf.SecuritySettings.OwnerPassword = "123password";

// Password to open the pdf
pdf.SecuritySettings.UserPassword = "password123";
pdf.SaveAs("protected.pdf");
C#
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