IronPDF vs XFINIUM.PDF: HTML to PDF Library Comparison for .NET

XFINIUM.PDF Specification

Standout Features of the IronPDF C# Library

Using Visual Studio

Visual Studio provides the NuGet Package Manager to install packages in your projects. Access it through the Project Menu or by right-clicking your project in Solution Explorer.

Figure 1. Accessing the NuGet Package Manager using the Project Menu in Visual Studio

Figure 2. Accessing the NuGet Package Manager using the context menu in Visual Studio

Once selected, browse for the IronPDF package and install it.

Figure 3. Installing the IronPDF library using the NuGET Package Manager in Visual Studio

Using the Developer Command Prompt

Install the IronPDF NuGet package through the Developer Command Prompt:

• Open the Developer Command Prompt

• Type the following command:

  nuget install IronPdf

  nuget install IronPdf

  SHELL
• Press Enter
• The package downloads and installs
• Reload your Visual Studio project

Download the NuGet Package Directly

Download and install IronPDF directly from NuGet:

• Go to to IronPdf NuGet Page
• Select Download Package
• Double-click the downloaded package
• The package installs
• Reload your Visual Studio project

Install IronPDF by Downloading the Library

Download the IronPDF .DLL file directly from the IronPDF Download.

Figure 4. Downloading the IronPDF Library DLL from the IronPDF website

Reference the library in your project:

• Right-click the Solution in Solution Explorer
• Select References
• Browse for the IronPDF.dll library
• Click OK

IronPDF is now ready to use. Let's install XFINIUM.PDF next.

Using IronPDF

// Create an instance of the ChromePdfRenderer
IronPdf.ChromePdfRenderer Renderer = new IronPdf.ChromePdfRenderer();

// Configure rendering options for better performance
Renderer.RenderingOptions.WaitFor.RenderDelay = 500; // Wait for JavaScript to load
Renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;

// Render a URL to PDF
using var Pdf = Renderer.RenderUrlAsPdf("___PROTECTED_URL_134___");

// Save the PDF with metadata
Pdf.MetaData.Author = "IronPDF";
Pdf.MetaData.Title = "Website to PDF Conversion";
Pdf.SaveAs("url.pdf");

// Create an instance of the ChromePdfRenderer
IronPdf.ChromePdfRenderer Renderer = new IronPdf.ChromePdfRenderer();

// Configure rendering options for better performance
Renderer.RenderingOptions.WaitFor.RenderDelay = 500; // Wait for JavaScript to load
Renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;

// Render a URL to PDF
using var Pdf = Renderer.RenderUrlAsPdf("___PROTECTED_URL_134___");

// Save the PDF with metadata
Pdf.MetaData.Author = "IronPDF";
Pdf.MetaData.Title = "Website to PDF Conversion";
Pdf.SaveAs("url.pdf");

// Create an instance of the ChromePdfRenderer
var Renderer = new IronPdf.ChromePdfRenderer();

// Configure rendering options
Renderer.RenderingOptions.MarginTop = 50; // millimeters
Renderer.RenderingOptions.MarginBottom = 50;
Renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;

// Render a simple HTML string to PDF
using var PDF = Renderer.RenderHtmlAsPdf("<h1>Html with CSS and Images</h1>");

// Add document properties
PDF.MetaData.Author = "Development Team";
PDF.MetaData.Keywords = "HTML, PDF, C#";
PDF.MetaData.ModifiedDate = DateTime.Now;

// Save the PDF
PDF.SaveAs("pixel-perfect.pdf");

// Load external HTML assets: images, CSS, and javascript
// An optional BasePath 'C:\site\assets\' is set as the file location to load assets from 
using var AdvancedPDF = Renderer.RenderHtmlAsPdf("<img src='icons/iron.png'>", @"C:\site\assets\");

// Apply security settings
AdvancedPDF.Password = "pass123";
AdvancedPDF.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.FullPrintRights;

// Save the advanced PDF with external assets
AdvancedPDF.SaveAs("html-with-assets.pdf");

// Create an instance of the ChromePdfRenderer
var Renderer = new IronPdf.ChromePdfRenderer();

// Configure rendering options
Renderer.RenderingOptions.MarginTop = 50; // millimeters
Renderer.RenderingOptions.MarginBottom = 50;
Renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;

// Render a simple HTML string to PDF
using var PDF = Renderer.RenderHtmlAsPdf("<h1>Html with CSS and Images</h1>");

// Add document properties
PDF.MetaData.Author = "Development Team";
PDF.MetaData.Keywords = "HTML, PDF, C#";
PDF.MetaData.ModifiedDate = DateTime.Now;

// Save the PDF
PDF.SaveAs("pixel-perfect.pdf");

// Load external HTML assets: images, CSS, and javascript
// An optional BasePath 'C:\site\assets\' is set as the file location to load assets from 
using var AdvancedPDF = Renderer.RenderHtmlAsPdf("<img src='icons/iron.png'>", @"C:\site\assets\");

// Apply security settings
AdvancedPDF.Password = "pass123";
AdvancedPDF.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.FullPrintRights;

// Save the advanced PDF with external assets
AdvancedPDF.SaveAs("html-with-assets.pdf");

Using XFINIUM.PDF

Creating a blank PDF document with XFINIUM.PDF requires three lines: create the document, create a page, and save:

// Create a new PDF document
PdfFixedDocument document = new PdfFixedDocument();

// Add a page to the document
PdfPage page = document.Pages.Add();

// Save the document as a PDF file
document.Save("empty.pdf");

// Create a new PDF document
PdfFixedDocument document = new PdfFixedDocument();

// Add a page to the document
PdfPage page = document.Pages.Add();

// Save the document as a PDF file
document.Save("empty.pdf");

Adding text content requires three additional lines: creating a font, creating a brush for color, and drawing text:

// Create a new PDF document
PdfFixedDocument document = new PdfFixedDocument();
PdfPage page = document.Pages.Add();

// Create a standard font with Helvetica face and 24 point size
PdfStandardFont helvetica = new PdfStandardFont(PdfStandardFontFace.Helvetica, 24);

// Create a solid RGB red brush.
PdfBrush brush = new PdfBrush(PdfRgbColor.Red);

// Draw the text on the page.
page.Graphics.DrawString("Hello World", helvetica, brush, 100, 100);

// Save the document as a PDF file
document.Save("helloworld.pdf");

// Create a new PDF document
PdfFixedDocument document = new PdfFixedDocument();
PdfPage page = document.Pages.Add();

// Create a standard font with Helvetica face and 24 point size
PdfStandardFont helvetica = new PdfStandardFont(PdfStandardFontFace.Helvetica, 24);

// Create a solid RGB red brush.
PdfBrush brush = new PdfBrush(PdfRgbColor.Red);

// Draw the text on the page.
page.Graphics.DrawString("Hello World", helvetica, brush, 100, 100);

// Save the document as a PDF file
document.Save("helloworld.pdf");

The object model closely resembles the PDF standard. This approach provides clear benefits for building complex abstractions like flow documents.## How to Create Fillable PDF Files

Using XFINIUM.PDF

XFINIUM.PDF allows you to create new PDF forms and fill existing PDF forms.

Each PDF form field type has a corresponding class:

• PdfTextBoxField – textbox fields
• PdfCheckBoxField – checkboxes
• PdfRadioButtonField – radio button sets
• PdfComboboxField – combo boxes
• PdfListboxField – listboxes
• PdfPushbuttonField – push buttons
• PdfSignatureField – signature fields

To create a form field, specify the field name and page location. After creating the field object, add it to the page and set its attributes:

// Create a text box field named "firstname"
PdfTextBoxField firstNameTextBox = new PdfTextBoxField("firstname");

// Add the field to a PDF page
pdfpage.Fields.Add(firstNameTextBox);

// Set the position of the field on the PDF page
firstNameTextBox.Widgets[0].VisualRectangle = new PdfVisualRectangle(150, 45, 200, 20);

// Create a text box field named "firstname"
PdfTextBoxField firstNameTextBox = new PdfTextBoxField("firstname");

// Add the field to a PDF page
pdfpage.Fields.Add(firstNameTextBox);

// Set the position of the field on the PDF page
firstNameTextBox.Widgets[0].VisualRectangle = new PdfVisualRectangle(150, 45, 200, 20);

To fill existing PDF forms, load them into a PdfFixedDocument object. The document's fields collection populates automatically. You can find fields by index or name and fill them by setting value properties:

// Load an existing PDF document with forms
PdfFixedDocument document = new PdfFixedDocument("form.pdf");

// Fill form fields with values
(document.Form.Fields["firstname"] as PdfTextBoxField).Text = "John";
(document.Form.Fields["lastname"] as PdfTextBoxField).Value = "Doe";
(document.Form.Fields["sex"].Widgets[0] as PdfRadioButtonWidget).Checked = true;
(document.Form.Fields["firstcar"] as PdfComboBoxField).SelectedIndex = 0;
(document.Form.Fields["secondcar"] as PdfListBoxField).SelectedIndex = 1;
(document.Form.Fields["agree"] as PdfCheckBoxField).Checked = true;

// Save the filled form as a new PDF file
document.Save("form_filled.pdf");

// Load an existing PDF document with forms
PdfFixedDocument document = new PdfFixedDocument("form.pdf");

// Fill form fields with values
(document.Form.Fields["firstname"] as PdfTextBoxField).Text = "John";
(document.Form.Fields["lastname"] as PdfTextBoxField).Value = "Doe";
(document.Form.Fields["sex"].Widgets[0] as PdfRadioButtonWidget).Checked = true;
(document.Form.Fields["firstcar"] as PdfComboBoxField).SelectedIndex = 0;
(document.Form.Fields["secondcar"] as PdfListBoxField).SelectedIndex = 1;
(document.Form.Fields["agree"] as PdfCheckBoxField).Checked = true;

// Save the filled form as a new PDF file
document.Save("form_filled.pdf");

Using IronPDF

Here's how you can create fillable PDFs using IronPDF:

// PM> Install-Package IronPdf
using IronPdf;
using IronPdf.Rendering;

// Step 1. Creating a PDF with editable forms from HTML using form and input tags
var FormHtml = @"
<html>
    <head>
        <style>
            body { font-family: Arial, sans-serif; margin: 40px; }
            h2 { color: #333; }
            form { background: #f4f4f4; padding: 20px; border-radius: 8px; }
            input[type='text'] { 
                width: 100%; 
                padding: 8px; 
                margin: 10px 0;
                border: 1px solid #ddd;
                border-radius: 4px;
            }
            input[type='checkbox'] { margin-right: 10px; }
            select { width: 100%; padding: 8px; margin: 10px 0; }
        </style>
    </head>
    <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><br>
          Email:<br> <input type='text' name='email' value=''>
          <br><br>
          Subscribe to newsletter: <input type='checkbox' name='newsletter' value='yes'>
          <br><br>
          Country: 
          <select name='country'>
              <option value='usa'>United States</option>
              <option value='uk'>United Kingdom</option>
              <option value='canada'>Canada</option>
          </select>
        </form>
    </body>
</html>";

// Create a PDF renderer with form creation enabled
IronPdf.ChromePdfRenderer Renderer = new IronPdf.ChromePdfRenderer();
Renderer.RenderingOptions.CreatePdfFormsFromHtml = true;
Renderer.RenderingOptions.CssMediaType = PdfCssMediaType.Print;
Renderer.RenderingOptions.MarginTop = 20;
Renderer.RenderingOptions.MarginBottom = 20;

// Render the HTML as a PDF and save it
var pdfDocument = Renderer.RenderHtmlAsPdf(FormHtml);
pdfDocument.SaveAs("BasicForm.pdf");

// Step 2. Reading and Writing PDF form values.
var FormDocument = PdfDocument.FromFile("BasicForm.pdf");

// Get form field collection
var form = FormDocument.Form;

// Set and Read the value of the "firstname" field
var FirstNameField = form.FindFormField("firstname");
FirstNameField.Value = "Minnie";
Console.WriteLine("FirstNameField value: {0}", FirstNameField.Value);

// Set and Read the value of the "lastname" field
var LastNameField = form.FindFormField("lastname");
LastNameField.Value = "Mouse";
Console.WriteLine("LastNameField value: {0}", LastNameField.Value);

// Set email field
var EmailField = form.FindFormField("email");
EmailField.Value = "minnie.mouse@example.com";

// Set checkbox
var NewsletterField = form.FindFormField("newsletter");
NewsletterField.Value = "yes";

// Set dropdown selection
var CountryField = form.FindFormField("country");
CountryField.Value = "usa";

// Save the form with filled values
FormDocument.SaveAs("FilledForm.pdf");

// Step 3. Flattening the form (making it non-editable)
FormDocument.Form.Flatten();
FormDocument.SaveAs("FlattenedForm.pdf");

// PM> Install-Package IronPdf
using IronPdf;
using IronPdf.Rendering;

// Step 1. Creating a PDF with editable forms from HTML using form and input tags
var FormHtml = @"
<html>
    <head>
        <style>
            body { font-family: Arial, sans-serif; margin: 40px; }
            h2 { color: #333; }
            form { background: #f4f4f4; padding: 20px; border-radius: 8px; }
            input[type='text'] { 
                width: 100%; 
                padding: 8px; 
                margin: 10px 0;
                border: 1px solid #ddd;
                border-radius: 4px;
            }
            input[type='checkbox'] { margin-right: 10px; }
            select { width: 100%; padding: 8px; margin: 10px 0; }
        </style>
    </head>
    <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><br>
          Email:<br> <input type='text' name='email' value=''>
          <br><br>
          Subscribe to newsletter: <input type='checkbox' name='newsletter' value='yes'>
          <br><br>
          Country: 
          <select name='country'>
              <option value='usa'>United States</option>
              <option value='uk'>United Kingdom</option>
              <option value='canada'>Canada</option>
          </select>
        </form>
    </body>
</html>";

// Create a PDF renderer with form creation enabled
IronPdf.ChromePdfRenderer Renderer = new IronPdf.ChromePdfRenderer();
Renderer.RenderingOptions.CreatePdfFormsFromHtml = true;
Renderer.RenderingOptions.CssMediaType = PdfCssMediaType.Print;
Renderer.RenderingOptions.MarginTop = 20;
Renderer.RenderingOptions.MarginBottom = 20;

// Render the HTML as a PDF and save it
var pdfDocument = Renderer.RenderHtmlAsPdf(FormHtml);
pdfDocument.SaveAs("BasicForm.pdf");

// Step 2. Reading and Writing PDF form values.
var FormDocument = PdfDocument.FromFile("BasicForm.pdf");

// Get form field collection
var form = FormDocument.Form;

// Set and Read the value of the "firstname" field
var FirstNameField = form.FindFormField("firstname");
FirstNameField.Value = "Minnie";
Console.WriteLine("FirstNameField value: {0}", FirstNameField.Value);

// Set and Read the value of the "lastname" field
var LastNameField = form.FindFormField("lastname");
LastNameField.Value = "Mouse";
Console.WriteLine("LastNameField value: {0}", LastNameField.Value);

// Set email field
var EmailField = form.FindFormField("email");
EmailField.Value = "minnie.mouse@example.com";

// Set checkbox
var NewsletterField = form.FindFormField("newsletter");
NewsletterField.Value = "yes";

// Set dropdown selection
var CountryField = form.FindFormField("country");
CountryField.Value = "usa";

// Save the form with filled values
FormDocument.SaveAs("FilledForm.pdf");

// Step 3. Flattening the form (making it non-editable)
FormDocument.Form.Flatten();
FormDocument.SaveAs("FlattenedForm.pdf");

You start by creating a form with HTML formatting tags. The library handles the complexity when saving as PDF. Reading and writing form values is done using the FindFormField function. Your application can immediately use this feature to fill forms programmatically.

For advanced form handling, including digital signatures, see the Create PDF Forms tutorial.

Using XFINIUM.PDF

A signature field applies digital signatures in PDF files (PdfSignatureField class). Though the signature field appears on one page, the digital signature signs the entire document.

The signing process uses a PdfDigitalSignature object to set the signature attribute. The signature forms when saving the document based on the PDF file's binary layout.

PdfDigitalSignature provides the foundation for all XFINIUM signatures:

• PdfCmsDigitalSignature – CMS standard signature (inherits from PdfDigitalSignature)
• PdfPadesDigitalSignature – PADES standard signature (inherits from PdfCmsDigitalSignature)
• PdfInteractiveCmsDigitalSignature – CMS signature using hardware smartcard
• PdfInteractivePadesDigitalSignature – PADES with hardware smartcard support
• PdfDocumentTimeStamp – Document-level timestamp (inherits from PdfDigitalSignature)

Using IronPDF

Developers frequently ask about programmatically adding signatures to PDFs with IronPDF and C#. This can mean:

• Adding graphical signature images from files
• Cryptographically signing to prevent tampering
• Adding handwritten signature icons with cryptographic signing

The first approach involves stamping a signature PNG onto existing PDF pages. Use it for signatures or company stamps:

// Open an existing PDF document or create a new one
var Pdf = PdfDocument.FromFile(@"C:\Path\To\ASPX to PDF.pdf");

// Define an HTML stamp with a signature image
var SignatureStamp = new HtmlStamp()
{
    Html = "<img src='signature.png' />",
    Width = 150,
    Height = 50,
    Bottom = 300,
    Left = 85,
    ZIndex = HtmlStamp.StampLayer.OnTopOfExistingPDFContent
};

// Advanced stamp with styling
var StyledSignatureStamp = new HtmlStamp()
{
    Html = @"<div style='border: 2px solid #000; padding: 10px; background: rgba(255,255,255,0.9);'>
                <img src='signature.png' style='width: 120px;' />
                <p style='margin: 5px 0 0 0; font-size: 10px;'>Digitally Signed</p>
                <p style='margin: 0; font-size: 8px;'>{date}</p>
             </div>",
    Width = 150,
    Height = 100,
    Bottom = 50,
    Right = 50,
    ZIndex = HtmlStamp.StampLayer.OnTopOfExistingPDFContent
};

// Stamp the signature on the first page of the PDF
Pdf.StampHTML(SignatureStamp, 1);

// Or apply to all pages
Pdf.StampHTML(StyledSignatureStamp);

// Save the stamped PDF
Pdf.SaveAs(@"C:\Path\To\Stamped_PDF.pdf");

// Open an existing PDF document or create a new one
var Pdf = PdfDocument.FromFile(@"C:\Path\To\ASPX to PDF.pdf");

// Define an HTML stamp with a signature image
var SignatureStamp = new HtmlStamp()
{
    Html = "<img src='signature.png' />",
    Width = 150,
    Height = 50,
    Bottom = 300,
    Left = 85,
    ZIndex = HtmlStamp.StampLayer.OnTopOfExistingPDFContent
};

// Advanced stamp with styling
var StyledSignatureStamp = new HtmlStamp()
{
    Html = @"<div style='border: 2px solid #000; padding: 10px; background: rgba(255,255,255,0.9);'>
                <img src='signature.png' style='width: 120px;' />
                <p style='margin: 5px 0 0 0; font-size: 10px;'>Digitally Signed</p>
                <p style='margin: 0; font-size: 8px;'>{date}</p>
             </div>",
    Width = 150,
    Height = 100,
    Bottom = 50,
    Right = 50,
    ZIndex = HtmlStamp.StampLayer.OnTopOfExistingPDFContent
};

// Stamp the signature on the first page of the PDF
Pdf.StampHTML(SignatureStamp, 1);

// Or apply to all pages
Pdf.StampHTML(StyledSignatureStamp);

// Save the stamped PDF
Pdf.SaveAs(@"C:\Path\To\Stamped_PDF.pdf");

Cryptographically sign PDFs using .pfx and .p12 X509Certificate2 digital certificates with one line:

// 123456 below represents the signature password
new IronPdf.PdfSignature("CertificateFile.p12", "123456").SignPdfFile("ASPX to PDF.pdf");

// Or with more control
var signature = new IronPdf.PdfSignature("CertificateFile.p12", "123456")
{
    SigningContact = "john@example.com",
    SigningLocation = "New York, USA",
    SigningReason = "Contract Agreement"
};

// Load the PDF
var pdf = PdfDocument.FromFile("contract.pdf");

// Sign and save
pdf.SignPdfWithDigitalSignature(signature);
pdf.SaveAs("signed-contract.pdf");

// 123456 below represents the signature password
new IronPdf.PdfSignature("CertificateFile.p12", "123456").SignPdfFile("ASPX to PDF.pdf");

// Or with more control
var signature = new IronPdf.PdfSignature("CertificateFile.p12", "123456")
{
    SigningContact = "john@example.com",
    SigningLocation = "New York, USA",
    SigningReason = "Contract Agreement"
};

// Load the PDF
var pdf = PdfDocument.FromFile("contract.pdf");

// Sign and save
pdf.SignPdfWithDigitalSignature(signature);
pdf.SaveAs("signed-contract.pdf");

This advanced example combines .pfx / .p12 X509Certificate2 digital ID signing with handwritten signatures:

// Create a digital signature using a certificate file
var Signature = new IronPdf.PdfSignature("Iron.pfx", "123456");

// Render a PDF document to be signed
var Renderer = new ChromePdfRenderer();
Renderer.RenderingOptions.MarginBottom = 0;
Renderer.RenderingOptions.MarginTop = 0;
Renderer.RenderingOptions.EnableJavaScript = true;
Renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;

// Create PDF with security features
string html = @"<h1>Contract Agreement</h1>
                <p>This document is digitally signed and encrypted.</p>
                <p>Agreement Date: " + DateTime.Now.ToString("yyyy-MM-dd") + @"</p>";

PdfDocument doc = Renderer.RenderHtmlAsPdf(html);

// Configure optional signing options and a handwritten signature graphic
Signature.SigningContact = "support@ironsoftware.com";
Signature.SigningLocation = "Chicago, USA";
Signature.SigningReason = "To show how to sign a PDF";

// Load a handwritten signature image
Signature.LoadSignatureImageFromFile("handwriting.png");

// Advanced security: Set permissions
doc.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.NoPrint;
doc.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.NoEdit;
doc.SecuritySettings.AllowUserCopyPasteContent = false;

// Sign the PDF document with the digital signature
doc.SignPdfWithDigitalSignature(Signature);

// Add password protection
doc.Password = "userpassword";
doc.OwnerPassword = "ownerpassword";

// Save the signed PDF document
doc.SaveAs("Signed_ASPX_to_PDF.pdf");

// Create a digital signature using a certificate file
var Signature = new IronPdf.PdfSignature("Iron.pfx", "123456");

// Render a PDF document to be signed
var Renderer = new ChromePdfRenderer();
Renderer.RenderingOptions.MarginBottom = 0;
Renderer.RenderingOptions.MarginTop = 0;
Renderer.RenderingOptions.EnableJavaScript = true;
Renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;

// Create PDF with security features
string html = @"<h1>Contract Agreement</h1>
                <p>This document is digitally signed and encrypted.</p>
                <p>Agreement Date: " + DateTime.Now.ToString("yyyy-MM-dd") + @"</p>";

PdfDocument doc = Renderer.RenderHtmlAsPdf(html);

// Configure optional signing options and a handwritten signature graphic
Signature.SigningContact = "support@ironsoftware.com";
Signature.SigningLocation = "Chicago, USA";
Signature.SigningReason = "To show how to sign a PDF";

// Load a handwritten signature image
Signature.LoadSignatureImageFromFile("handwriting.png");

// Advanced security: Set permissions
doc.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.NoPrint;
doc.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.NoEdit;
doc.SecuritySettings.AllowUserCopyPasteContent = false;

// Sign the PDF document with the digital signature
doc.SignPdfWithDigitalSignature(Signature);

// Add password protection
doc.Password = "userpassword";
doc.OwnerPassword = "ownerpassword";

// Save the signed PDF document
doc.SaveAs("Signed_ASPX_to_PDF.pdf");

For complete security implementations, explore Ironsecuredoc Documentation for advanced document protection features.## How Does Each Library Handle Modern CSS Frameworks and Bootstrap?

Modern web applications often rely on CSS frameworks like Bootstrap for quick UI development and responsive design. PDF generation tools must accurately preserve these framework layouts to ensure professional document quality.

IronPDF: Complete Bootstrap Framework Support

IronPDF's Chromium rendering engine fully supports modern CSS frameworks:

• Bootstrap 5: Full flexbox and CSS Grid rendering with all responsive components
• Bootstrap 4: Complete card systems, navigation bars, and utility classes
• Tailwind CSS: All utility-first classes and responsive variants
• Foundation and Other Frameworks: Full CSS3 support means all modern frameworks work correctly
• Advanced CSS: Flexbox, CSS Grid, custom properties, animations, and transforms

Real-world validation: The Bootstrap homepage and templates convert with browser-accurate fidelity.

Code Example: Event Schedule with Bootstrap Cards

using IronPdf;

var renderer = new ChromePdfRenderer();

// Configure rendering for optimal Bootstrap output
renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;
renderer.RenderingOptions.EnableJavaScript = true;
renderer.RenderingOptions.RenderDelay = 500; // Allow JS to fully load
renderer.RenderingOptions.ViewPortWidth = 1280; // Desktop viewport
renderer.RenderingOptions.MarginTop = 10;
renderer.RenderingOptions.MarginBottom = 10;
renderer.RenderingOptions.MarginLeft = 10;
renderer.RenderingOptions.MarginRight = 10;

string bootstrapSchedule = @"
<!DOCTYPE html>
<html>
<head>
    <link href='___PROTECTED_URL_135___ rel='stylesheet'>
    <style>
        @media print {
            .pagebreak { page-break-after: always; }
        }
    </style>
</head>
<body>
    <div class='container my-5'>
        <h1 class='text-center mb-5'>Tech Conference 2025 - Schedule</h1>

        <div class='row g-4'>
            <div class='col-md-6'>
                <div class='card border-primary'>
                    <div class='card-header bg-primary text-white d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Keynote Session</h5>
                        <span class='badge bg-light text-primary'>9:00 AM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Main Auditorium</h6>
                        <p class='card-text'><strong>The Future of AI in Software Development</strong></p>
                        <p class='card-text'>Join us for an exploration of how artificial intelligence is transforming the software development environment.</p>
                        <div class='d-flex align-items-center'>
                            <img src='___PROTECTED_URL_136___ class='rounded-circle me-2' alt='Speaker'>
                            <div>
                                <div class='fw-bold'>Dr. Sarah Chen</div>
                                <small class='text-muted'>AI Research Lead</small>
                            </div>
                        </div>
                    </div>
                </div>
            </div>

            <div class='col-md-6'>
                <div class='card border-success'>
                    <div class='card-header bg-success text-white d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Workshop</h5>
                        <span class='badge bg-light text-success'>10:30 AM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Workshop Room A</h6>
                        <p class='card-text'><strong>Hands-On: Cloud-Native Architecture</strong></p>
                        <p class='card-text'>Learn practical techniques for building flexible, cloud-native applications with modern frameworks.</p>
                        <div class='d-flex align-items-center'>
                            <img src='___PROTECTED_URL_137___ class='rounded-circle me-2' alt='Speaker'>
                            <div>
                                <div class='fw-bold'>Michael Rodriguez</div>
                                <small class='text-muted'>Cloud Architect</small>
                            </div>
                        </div>
                    </div>
                </div>
            </div>

            <div class='col-md-6'>
                <div class='card border-warning'>
                    <div class='card-header bg-warning text-dark d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Panel Discussion</h5>
                        <span class='badge bg-dark'>2:00 PM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Main Auditorium</h6>
                        <p class='card-text'><strong>Security in Modern Web Applications</strong></p>
                        <p class='card-text'>Industry experts discuss current security challenges and best practices for protecting user data.</p>
                        <small class='text-muted'>Featuring 4 industry experts</small>
                    </div>
                </div>
            </div>

            <div class='col-md-6'>
                <div class='card border-info'>
                    <div class='card-header bg-info text-white d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Technical Talk</h5>
                        <span class='badge bg-light text-info'>3:30 PM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Room B</h6>
                        <p class='card-text'><strong>Performance Optimization Strategies</strong></p>
                        <p class='card-text'>Deep dive into advanced techniques for improve application performance and reducing latency.</p>
                        <div class='d-flex align-items-center'>
                            <img src='___PROTECTED_URL_138___ class='rounded-circle me-2' alt='Speaker'>
                            <div>
                                <div class='fw-bold'>Alex Kim</div>
                                <small class='text-muted'>Performance Engineer</small>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>

        <div class='pagebreak'></div>

        <h2 class='mt-5'>Additional Sessions</h2>
        <div class='table-responsive'>
            <table class='table table-striped'>
                <thead>
                    <tr>
                        <th>Time</th>
                        <th>Session</th>
                        <th>Speaker</th>
                        <th>Location</th>
                    </tr>
                </thead>
                <tbody>
                    <tr>
                        <td>11:45 AM</td>
                        <td>Lightning Talks</td>
                        <td>Various</td>
                        <td>Room C</td>
                    </tr>
                    <tr>
                        <td>1:00 PM</td>
                        <td>Networking Lunch</td>
                        <td>-</td>
                        <td>Cafeteria</td>
                    </tr>
                </tbody>
            </table>
        </div>
    </div>
</body>
</html>";

// Generate the PDF
var pdf = renderer.RenderHtmlAsPdf(bootstrapSchedule);

// Add metadata
pdf.MetaData.Author = "Tech Conference Team";
pdf.MetaData.Title = "Conference Schedule 2025";
pdf.MetaData.Subject = "Event Schedule";

// Save the PDF
pdf.SaveAs("conference-schedule.pdf");

// Example: Generate responsive invoice with Bootstrap
string bootstrapInvoice = @"
<!DOCTYPE html>
<html>
<head>
    <link href='___PROTECTED_URL_139___ rel='stylesheet'>
    <link href='___PROTECTED_URL_140___ rel='stylesheet'>
</head>
<body>
    <div class='container mt-5'>
        <div class='row'>
            <div class='col-12'>
                <div class='card'>
                    <div class='card-body'>
                        <div class='row mb-4'>
                            <div class='col-sm-6'>
                                <h2 class='text-primary'><i class='fas fa-file-invoice'></i> INVOICE</h2>
                                <p class='mb-1'><strong>Invoice #:</strong> INV-2025-001</p>
                                <p class='mb-1'><strong>Date:</strong> " + DateTime.Now.ToString("MMMM dd, yyyy") + @"</p>
                            </div>
                            <div class='col-sm-6 text-sm-end'>
                                <h4>Your Company Name</h4>
                                <p class='mb-1'>123 Business St</p>
                                <p class='mb-1'>City, State 12345</p>
                                <p>contact@company.com</p>
                            </div>
                        </div>

                        <hr>

                        <div class='row mb-4'>
                            <div class='col-sm-6'>
                                <h5>Bill To:</h5>
                                <p class='mb-1'><strong>Client Company</strong></p>
                                <p class='mb-1'>456 Client Ave</p>
                                <p>City, State 67890</p>
                            </div>
                        </div>

                        <div class='table-responsive'>
                            <table class='table table-bordered'>
                                <thead class='table-primary'>
                                    <tr>
                                        <th>Description</th>
                                        <th class='text-center'>Quantity</th>
                                        <th class='text-end'>Price</th>
                                        <th class='text-end'>Total</th>
                                    </tr>
                                </thead>
                                <tbody>
                                    <tr>
                                        <td>Web Development Services</td>
                                        <td class='text-center'>40</td>
                                        <td class='text-end'>$150.00</td>
                                        <td class='text-end'>$6,000.00</td>
                                    </tr>
                                    <tr>
                                        <td>UI/UX Design</td>
                                        <td class='text-center'>20</td>
                                        <td class='text-end'>$125.00</td>
                                        <td class='text-end'>$2,500.00</td>
                                    </tr>
                                </tbody>
                                <tfoot>
                                    <tr>
                                        <td colspan='3' class='text-end'><strong>Subtotal:</strong></td>
                                        <td class='text-end'><strong>$8,500.00</strong></td>
                                    </tr>
                                    <tr>
                                        <td colspan='3' class='text-end'>Tax (10%):</td>
                                        <td class='text-end'>$850.00</td>
                                    </tr>
                                    <tr class='table-primary'>
                                        <td colspan='3' class='text-end'><strong>Total Due:</strong></td>
                                        <td class='text-end'><strong>$9,350.00</strong></td>
                                    </tr>
                                </tfoot>
                            </table>
                        </div>

                        <div class='alert alert-info mt-4'>
                            <i class='fas fa-info-circle'></i> Payment is due within 30 days. Thank you for your business!
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
</body>
</html>";

var invoicePdf = renderer.RenderHtmlAsPdf(bootstrapInvoice);
invoicePdf.SaveAs("bootstrap-invoice.pdf");

using IronPdf;

var renderer = new ChromePdfRenderer();

// Configure rendering for optimal Bootstrap output
renderer.RenderingOptions.CssMediaType = IronPdf.Rendering.PdfCssMediaType.Print;
renderer.RenderingOptions.EnableJavaScript = true;
renderer.RenderingOptions.RenderDelay = 500; // Allow JS to fully load
renderer.RenderingOptions.ViewPortWidth = 1280; // Desktop viewport
renderer.RenderingOptions.MarginTop = 10;
renderer.RenderingOptions.MarginBottom = 10;
renderer.RenderingOptions.MarginLeft = 10;
renderer.RenderingOptions.MarginRight = 10;

string bootstrapSchedule = @"
<!DOCTYPE html>
<html>
<head>
    <link href='___PROTECTED_URL_135___ rel='stylesheet'>
    <style>
        @media print {
            .pagebreak { page-break-after: always; }
        }
    </style>
</head>
<body>
    <div class='container my-5'>
        <h1 class='text-center mb-5'>Tech Conference 2025 - Schedule</h1>

        <div class='row g-4'>
            <div class='col-md-6'>
                <div class='card border-primary'>
                    <div class='card-header bg-primary text-white d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Keynote Session</h5>
                        <span class='badge bg-light text-primary'>9:00 AM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Main Auditorium</h6>
                        <p class='card-text'><strong>The Future of AI in Software Development</strong></p>
                        <p class='card-text'>Join us for an exploration of how artificial intelligence is transforming the software development environment.</p>
                        <div class='d-flex align-items-center'>
                            <img src='___PROTECTED_URL_136___ class='rounded-circle me-2' alt='Speaker'>
                            <div>
                                <div class='fw-bold'>Dr. Sarah Chen</div>
                                <small class='text-muted'>AI Research Lead</small>
                            </div>
                        </div>
                    </div>
                </div>
            </div>

            <div class='col-md-6'>
                <div class='card border-success'>
                    <div class='card-header bg-success text-white d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Workshop</h5>
                        <span class='badge bg-light text-success'>10:30 AM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Workshop Room A</h6>
                        <p class='card-text'><strong>Hands-On: Cloud-Native Architecture</strong></p>
                        <p class='card-text'>Learn practical techniques for building flexible, cloud-native applications with modern frameworks.</p>
                        <div class='d-flex align-items-center'>
                            <img src='___PROTECTED_URL_137___ class='rounded-circle me-2' alt='Speaker'>
                            <div>
                                <div class='fw-bold'>Michael Rodriguez</div>
                                <small class='text-muted'>Cloud Architect</small>
                            </div>
                        </div>
                    </div>
                </div>
            </div>

            <div class='col-md-6'>
                <div class='card border-warning'>
                    <div class='card-header bg-warning text-dark d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Panel Discussion</h5>
                        <span class='badge bg-dark'>2:00 PM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Main Auditorium</h6>
                        <p class='card-text'><strong>Security in Modern Web Applications</strong></p>
                        <p class='card-text'>Industry experts discuss current security challenges and best practices for protecting user data.</p>
                        <small class='text-muted'>Featuring 4 industry experts</small>
                    </div>
                </div>
            </div>

            <div class='col-md-6'>
                <div class='card border-info'>
                    <div class='card-header bg-info text-white d-flex justify-content-between align-items-center'>
                        <h5 class='mb-0'>Technical Talk</h5>
                        <span class='badge bg-light text-info'>3:30 PM</span>
                    </div>
                    <div class='card-body'>
                        <h6 class='card-subtitle mb-2 text-muted'>Room B</h6>
                        <p class='card-text'><strong>Performance Optimization Strategies</strong></p>
                        <p class='card-text'>Deep dive into advanced techniques for improve application performance and reducing latency.</p>
                        <div class='d-flex align-items-center'>
                            <img src='___PROTECTED_URL_138___ class='rounded-circle me-2' alt='Speaker'>
                            <div>
                                <div class='fw-bold'>Alex Kim</div>
                                <small class='text-muted'>Performance Engineer</small>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>

        <div class='pagebreak'></div>

        <h2 class='mt-5'>Additional Sessions</h2>
        <div class='table-responsive'>
            <table class='table table-striped'>
                <thead>
                    <tr>
                        <th>Time</th>
                        <th>Session</th>
                        <th>Speaker</th>
                        <th>Location</th>
                    </tr>
                </thead>
                <tbody>
                    <tr>
                        <td>11:45 AM</td>
                        <td>Lightning Talks</td>
                        <td>Various</td>
                        <td>Room C</td>
                    </tr>
                    <tr>
                        <td>1:00 PM</td>
                        <td>Networking Lunch</td>
                        <td>-</td>
                        <td>Cafeteria</td>
                    </tr>
                </tbody>
            </table>
        </div>
    </div>
</body>
</html>";

// Generate the PDF
var pdf = renderer.RenderHtmlAsPdf(bootstrapSchedule);

// Add metadata
pdf.MetaData.Author = "Tech Conference Team";
pdf.MetaData.Title = "Conference Schedule 2025";
pdf.MetaData.Subject = "Event Schedule";

// Save the PDF
pdf.SaveAs("conference-schedule.pdf");

// Example: Generate responsive invoice with Bootstrap
string bootstrapInvoice = @"
<!DOCTYPE html>
<html>
<head>
    <link href='___PROTECTED_URL_139___ rel='stylesheet'>
    <link href='___PROTECTED_URL_140___ rel='stylesheet'>
</head>
<body>
    <div class='container mt-5'>
        <div class='row'>
            <div class='col-12'>
                <div class='card'>
                    <div class='card-body'>
                        <div class='row mb-4'>
                            <div class='col-sm-6'>
                                <h2 class='text-primary'><i class='fas fa-file-invoice'></i> INVOICE</h2>
                                <p class='mb-1'><strong>Invoice #:</strong> INV-2025-001</p>
                                <p class='mb-1'><strong>Date:</strong> " + DateTime.Now.ToString("MMMM dd, yyyy") + @"</p>
                            </div>
                            <div class='col-sm-6 text-sm-end'>
                                <h4>Your Company Name</h4>
                                <p class='mb-1'>123 Business St</p>
                                <p class='mb-1'>City, State 12345</p>
                                <p>contact@company.com</p>
                            </div>
                        </div>

                        <hr>

                        <div class='row mb-4'>
                            <div class='col-sm-6'>
                                <h5>Bill To:</h5>
                                <p class='mb-1'><strong>Client Company</strong></p>
                                <p class='mb-1'>456 Client Ave</p>
                                <p>City, State 67890</p>
                            </div>
                        </div>

                        <div class='table-responsive'>
                            <table class='table table-bordered'>
                                <thead class='table-primary'>
                                    <tr>
                                        <th>Description</th>
                                        <th class='text-center'>Quantity</th>
                                        <th class='text-end'>Price</th>
                                        <th class='text-end'>Total</th>
                                    </tr>
                                </thead>
                                <tbody>
                                    <tr>
                                        <td>Web Development Services</td>
                                        <td class='text-center'>40</td>
                                        <td class='text-end'>$150.00</td>
                                        <td class='text-end'>$6,000.00</td>
                                    </tr>
                                    <tr>
                                        <td>UI/UX Design</td>
                                        <td class='text-center'>20</td>
                                        <td class='text-end'>$125.00</td>
                                        <td class='text-end'>$2,500.00</td>
                                    </tr>
                                </tbody>
                                <tfoot>
                                    <tr>
                                        <td colspan='3' class='text-end'><strong>Subtotal:</strong></td>
                                        <td class='text-end'><strong>$8,500.00</strong></td>
                                    </tr>
                                    <tr>
                                        <td colspan='3' class='text-end'>Tax (10%):</td>
                                        <td class='text-end'>$850.00</td>
                                    </tr>
                                    <tr class='table-primary'>
                                        <td colspan='3' class='text-end'><strong>Total Due:</strong></td>
                                        <td class='text-end'><strong>$9,350.00</strong></td>
                                    </tr>
                                </tfoot>
                            </table>
                        </div>

                        <div class='alert alert-info mt-4'>
                            <i class='fas fa-info-circle'></i> Payment is due within 30 days. Thank you for your business!
                        </div>
                    </div>
                </div>
            </div>
        </div>
    </div>
</body>
</html>";

var invoicePdf = renderer.RenderHtmlAsPdf(bootstrapInvoice);
invoicePdf.SaveAs("bootstrap-invoice.pdf");

Output: A professional conference schedule with Bootstrap's card grid, flexbox alignment, badge components, and responsive layout—all accurately rendered in the PDF.

XFINIUM.PDF: Limited HTML and Framework Support

XFINIUM.PDF focuses on PDF generation and manipulation rather than HTML-to-PDF conversion. The library has significant limitations for Bootstrap and modern CSS frameworks:

• No Native HTML Rendering: XFINIUM.PDF does not include a built-in HTML-to-PDF conversion engine
• Basic HTML Support Only: Limited to simple HTML structures without advanced CSS
• No Bootstrap Support: Modern Bootstrap frameworks (4/5) with flexbox and CSS Grid are not supported
• Workarounds Required: Developers must use low-level PDF APIs to manually recreate layouts
• External Tools Needed: May require integration with external HTML rendering engines

Development impact: Applications using Bootstrap or modern CSS frameworks cannot directly convert their UI to PDF with XFINIUM.PDF. Developers must either:

1. Recreate layouts using XFINIUM.PDF's low-level drawing APIs (significant development time)
2. Integrate external HTML rendering tools (added complexity and dependencies)
3. Maintain separate PDF layout code parallel to web UI (maintenance overhead)

For projects requiring HTML-to-PDF conversion with modern frameworks, XFINIUM.PDF's limitations require significant additional development.

For complete Bootstrap and modern CSS framework support, see the Bootstrap & Flexbox CSS Guide.

XFINIUM.PDF Pricing and Licensing

Each package comes in two editions: Generator Edition for PDF production/editing, and Viewer Edition containing all Generator features plus PDF rendering and viewing.

• Each developer needs a license.
• Royalty-free distribution to unlimited desktops/servers.
• Assistance Subscription includes one year of updates/support.

Pricing ranges from $290.00 to $872.00 per year.

IronPDF Pricing and Licensing

IronPDF is free for development and can be licensed for commercial use anytime. Options include single-project licenses, single developers, agencies, multinational organizations, and SaaS/OEM redistribution. All licenses include a 30-day money-back guarantee, one year of support/upgrades, dev/staging/production validity, and a perpetual license (one-time purchase). The Lite package starts at $799 with no recurring expenses.