using IronPdf; // Disable local disk access or cross-origin requests Installation.EnableWebSecurity = true; // Instantiate Renderer var renderer = new ChromePdfRenderer(); // Create a PDF from a HTML string using C# var pdf = renderer.RenderHtmlAsPdf("<h1>Hello World</h1>"); // Export to a file or Stream pdf.SaveAs("output.pdf"); // Advanced Example with HTML Assets // Load external html assets: Images, CSS and JavaScript. // An optional BasePath 'C:\site\assets\' is set as the file location to load assets from var myAdvancedPdf = renderer.RenderHtmlAsPdf("<img src='icons/iron.png'>", @"C:\site\assets\"); myAdvancedPdf.SaveAs("html-with-assets.pdf");

PRODUCT COMPARISONS

Generate PDF Using iTextSharp in MVC vs IronPDF: A Complete Comparison

Curtis Chau

Published:November 27, 2025

Creating PDF documents in ASP.NET MVC applications is a common requirement for generating reports, invoices, and downloadable content. While iTextSharp has been a popular choice for years, IronPDF offers a modern alternative with superior HTML rendering capabilities. Let's explore both approaches to help you make an informed decision.

How Do You Generate PDF Using iTextSharp in MVC?

To generate PDF files using iTextSharp in your ASP.NET MVC application, you'll first need to install the iTextSharp library either through its NuGet package or the iTextSharp DLL. The iTextSharp library provides low-level control over PDF creation through its Document class and object model.

The following code provides a basic example of creating PDFs with iTextSharp:

public ActionResult GeneratePDF()
{
    Document DOC = new Document(PageSize.A4);
    MemoryStream memoryStream = new MemoryStream();
    PdfWriter writer = PdfWriter.GetInstance(doc, memoryStream);
    doc.Open();
    doc.Add(new Paragraph("Hello World"));
    doc.Add(new Paragraph("This is a PDF document created with iTextSharp"));
    doc.Close();
    byte[] pdfBytes = memoryStream.ToArray();
    Response.AppendHeader("Content-Disposition", "inline; filename=document.pdf");
    return File(pdfBytes, "application/pdf");
}

public ActionResult GeneratePDF()
{
    Document DOC = new Document(PageSize.A4);
    MemoryStream memoryStream = new MemoryStream();
    PdfWriter writer = PdfWriter.GetInstance(doc, memoryStream);
    doc.Open();
    doc.Add(new Paragraph("Hello World"));
    doc.Add(new Paragraph("This is a PDF document created with iTextSharp"));
    doc.Close();
    byte[] pdfBytes = memoryStream.ToArray();
    Response.AppendHeader("Content-Disposition", "inline; filename=document.pdf");
    return File(pdfBytes, "application/pdf");
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

iTextSharp Simple PDF File Output

Generate PDF Using iTextSharp in MVC vs IronPDF: A Complete Comparison: Image 1 - iTextSharp simple output PDF document

This code demonstrates the fundamental approach: create a new instance of the Document, attach a PdfWriter to a file stream, add content using elements, and then return the PDF file through an action method in your Controller. This lets you save the data to the server or let the user download the file in the correct format.

What Are the Challenges with HTML to PDF Conversion with the iTextSharp Library?

While iTextSharp excels at programmatic PDF creation, converting HTML to PDF presents significant challenges. The deprecated HTMLWorker class and its replacement XMLWorker have limited CSS support and struggle with modern web content.

// Converting HTML with iTextSharp - limited CSS support
public ActionResult ConvertHtml(string htmlString)
{
    Document pdfDoc = new Document(PageSize.A4);
    MemoryStream stream = new MemoryStream();
    PdfWriter writer = PdfWriter.GetInstance(pdfDoc, stream);
    pdfDoc.Open();
    // XMLWorker has limited CSS3 support
    using (var stringReader = new StringReader(htmlString))
    {
        XMLWorkerHelper.GetInstance().ParseXHtml(writer, pdfDoc, stringReader);
    }
    pdfDoc.Close();
    return File(stream.ToArray(), "application/pdf");
}

// Converting HTML with iTextSharp - limited CSS support
public ActionResult ConvertHtml(string htmlString)
{
    Document pdfDoc = new Document(PageSize.A4);
    MemoryStream stream = new MemoryStream();
    PdfWriter writer = PdfWriter.GetInstance(pdfDoc, stream);
    pdfDoc.Open();
    // XMLWorker has limited CSS3 support
    using (var stringReader = new StringReader(htmlString))
    {
        XMLWorkerHelper.GetInstance().ParseXHtml(writer, pdfDoc, stringReader);
    }
    pdfDoc.Close();
    return File(stream.ToArray(), "application/pdf");
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

iTextSharp HTML to PDF Output

Generate PDF Using iTextSharp in MVC vs IronPDF: A Complete Comparison: Image 2 - PDF rendered from HTML content with iTextSharp

The limitations become apparent when working with Bootstrap layouts, JavaScript-rendered content, or complex CSS3 styling. Creating PDF documents with modern HTML requires extensive workarounds or alternative approaches, which often use external tools.

How Does IronPDF Simplify PDF Generation in ASP.NET MVC?

IronPDF transforms PDF generation by using a Chrome rendering engine, ensuring pixel-perfect HTML to PDF conversion. Install the IronPDF NuGet package to get started with a more streamlined approach in your Visual Studio project.

using IronPdf;
public ActionResult GeneratePdfWithIronPDF()
{
    var renderer = new ChromePdfRenderer();
    // Convert HTML string with full CSS3 and JavaScript support
    var PDF = renderer.RenderHtmlAsPdf(@"
        <html>
            <head>
                <link href='https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css' rel='stylesheet'>
                <style>
                    .gradient { background: linear-gradient(45deg, #667eea 0%, #764ba2 100%); }
                </style>
            </head>
            <body>
                <div class='container mt-5'>
                    <div class='card gradient text-white'>
                        <div class='card-body'>
                            <h1>Modern PDF Generation</h1>
                            <p>Full CSS3, Bootstrap, and JavaScript support</p>
                        </div>
                    </div>
                </div>
            </body>
        </html>");
    return File(pdf.BinaryData, "application/pdf", "modern.pdf");
}

using IronPdf;
public ActionResult GeneratePdfWithIronPDF()
{
    var renderer = new ChromePdfRenderer();
    // Convert HTML string with full CSS3 and JavaScript support
    var PDF = renderer.RenderHtmlAsPdf(@"
        <html>
            <head>
                <link href='https://cdn.jsdelivr.net/npm/bootstrap@5.0.2/dist/css/bootstrap.min.css' rel='stylesheet'>
                <style>
                    .gradient { background: linear-gradient(45deg, #667eea 0%, #764ba2 100%); }
                </style>
            </head>
            <body>
                <div class='container mt-5'>
                    <div class='card gradient text-white'>
                        <div class='card-body'>
                            <h1>Modern PDF Generation</h1>
                            <p>Full CSS3, Bootstrap, and JavaScript support</p>
                        </div>
                    </div>
                </div>
            </body>
        </html>");
    return File(pdf.BinaryData, "application/pdf", "modern.pdf");
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

Created PDF with IronPDF

Generate PDF Using iTextSharp in MVC vs IronPDF: A Complete Comparison: Image 3 - IronPDF output PDF file

The ChromePdfRenderer handles complex layouts effortlessly, maintaining the visual fidelity of your HTML content in the resulting PDF documents.

Which Approach Offers Better MVC Integration?

Both libraries support ASP.NET MVC patterns, but IronPDF excels with Razor Engine view rendering. You can convert entire views, like your Index View, directly to PDF:

// IronPDF - Direct Razor view to PDF conversion
public IActionResult Index()
{
    var renderer = new ChromePdfRenderer();
    // Render MVC view to PDF
    PdfDocument PDF = renderer.RenderRazorViewToPdf(this._razorViewRenderer, "./Views/Home/Index.cshtml");
    return File(pdf.BinaryData, "application/pdf", "Home-Index.pdf");
}

// IronPDF - Direct Razor view to PDF conversion
public IActionResult Index()
{
    var renderer = new ChromePdfRenderer();
    // Render MVC view to PDF
    PdfDocument PDF = renderer.RenderRazorViewToPdf(this._razorViewRenderer, "./Views/Home/Index.cshtml");
    return File(pdf.BinaryData, "application/pdf", "Home-Index.pdf");
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

Rendered Razor View to PDF

Generate PDF Using iTextSharp in MVC vs IronPDF: A Complete Comparison: Image 4 - IronPDF output for Razor View to PDF

Compare this to iTextSharp's approach, which requires manual building of the document structure in the Controller. This means you are manually building the document from the source code for the desired page size:

// iTextSharp - Manual PDF construction
public ActionResult InvoicePdfTextSharp(int id)
{
    var model = GetInvoiceData(id);
    Document document = new Document();
    MemoryStream stream = new MemoryStream();
    PdfWriter.GetInstance(document, stream);
    document.Open();
    // Manually add each element
    document.Add(new Paragraph($"Invoice #{model.InvoiceNumber}"));
    document.Add(new Paragraph($"Date: {model.Date}"));
    // ... continue building PDF structure
    document.Close();
    return new FileContentResult(stream.ToArray(), "application/pdf");
}

// iTextSharp - Manual PDF construction
public ActionResult InvoicePdfTextSharp(int id)
{
    var model = GetInvoiceData(id);
    Document document = new Document();
    MemoryStream stream = new MemoryStream();
    PdfWriter.GetInstance(document, stream);
    document.Open();
    // Manually add each element
    document.Add(new Paragraph($"Invoice #{model.InvoiceNumber}"));
    document.Add(new Paragraph($"Date: {model.Date}"));
    // ... continue building PDF structure
    document.Close();
    return new FileContentResult(stream.ToArray(), "application/pdf");
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

How Do You Handle File Downloads and Streaming to Create a PDF?

Both libraries support various output methods for PDF files in your web applications. Here's how to implement file download with proper content disposition headers, which typically involves public byte arrays to pass the file data to the browser:

// Common reference pattern for both libraries
public ActionResult DownloadPdf()
{
    byte[] pdfData = GeneratePdfContent(); // Your PDF generation logic
    Response.AppendHeader("Content-Length", pdfData.Length.ToString());
    Response.AppendHeader("Content-Disposition", "attachment; filename=download.pdf");
    return new FileContentResult(pdfData, "application/pdf");
}

// Common reference pattern for both libraries
public ActionResult DownloadPdf()
{
    byte[] pdfData = GeneratePdfContent(); // Your PDF generation logic
    Response.AppendHeader("Content-Length", pdfData.Length.ToString());
    Response.AppendHeader("Content-Disposition", "attachment; filename=download.pdf");
    return new FileContentResult(pdfData, "application/pdf");
}

IRON VB CONVERTER ERROR developers@ironsoftware.com

$vbLabelText $csharpLabel

What About Licensing and Project Considerations?

The iTextSharp library uses an AGPL license for its open-source version, which requires your own implementation to be open-source. Commercial licenses are available for proprietary processes. IronPDF offers a commercial licensing model with a free trial for development and testing. If you need to delete a file, the file must first be released by the system.

For new projects requiring HTML to PDF conversion with modern web standards support, IronPDF empowers developers with its Chrome-based rendering. Legacy projects already using iTextSharp for basic PDF creation might continue with their existing implementation unless HTML rendering becomes necessary.

Conclusion

While iTextSharp provides granular control for programmatic PDF creation, IronPDF excels at converting HTML to professional PDF documents. The choice depends on your specific needs: use iTextSharp for simple, code-driven PDF generation where you control every element, or choose IronPDF for seamless HTML to PDF conversion with full CSS3 and JavaScript support.

Ready to modernize your PDF generation? Get started with IronPDF's free trial and experience the difference in your ASP.NET .NET MVC applications.

Curtis Chau

Chat with engineering team now

Technical Writer

Curtis Chau holds a Bachelor’s degree in Computer Science (Carleton University) and specializes in front-end development with expertise in Node.js, TypeScript, JavaScript, and React. Passionate about crafting intuitive and aesthetically pleasing user interfaces, Curtis enjoys working with modern frameworks and creating well-structured, visually appealing manuals.

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