PDF SDK .NET Alternative: Why Developers Choose IronPDF

What Should Developers Look for in a .NET PDF Library?

A capable .NET PDF library must deliver cross-platform support across .NET Framework, .NET Core, and .NET Standard while maintaining low memory usage during batch processing. Unlike heavyweight PDF SDKs that require extensive configuration, the best .NET PDF SDK alternatives deliver high-quality output through an intuitive API that developers can implement in just a few lines of code.

IronPDF stands apart from traditional PDF SDKs by offering:

• PDF creation from HTML strings, URLs, ASPX pages, and image formats
• Form fill capabilities for both standard AcroForms and XFA forms
• Full document security with AES encryption and permission controls
• Digital signatures using .pfx certificates for document authenticity
• Support for PDF/A standards, enabling long-term archiving compliance

The library runs natively in Visual Studio and deploys seamlessly to Azure, AWS, Docker, and Linux development environments. With mixed raster content (MRC) compression, IronPDF optimizes file size while preserving image quality across color spaces.

// Create a PDF document from HTML with form fields
using IronPdf;
class Program
{
    static void Main(string[] args)
    {
        var renderer = new ChromePdfRenderer();
        // Configure rendering for high quality output
        renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;
        renderer.RenderingOptions.MarginTop = 20;
        renderer.RenderingOptions.MarginBottom = 20;
        // Render HTML with form fields to PDF
        string htmlContent = @"
            <h1>Customer Registration</h1>
            <form>
                <label>Name:</label>
                <label>Email:</label>
            </form>";
        PdfDocument pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("registration-form.pdf");
    }
}

// Create a PDF document from HTML with form fields
using IronPdf;
class Program
{
    static void Main(string[] args)
    {
        var renderer = new ChromePdfRenderer();
        // Configure rendering for high quality output
        renderer.RenderingOptions.PaperSize = IronPdf.Rendering.PdfPaperSize.A4;
        renderer.RenderingOptions.MarginTop = 20;
        renderer.RenderingOptions.MarginBottom = 20;
        // Render HTML with form fields to PDF
        string htmlContent = @"
            <h1>Customer Registration</h1>
            <form>
                <label>Name:</label>
                <label>Email:</label>
            </form>";
        PdfDocument pdf = renderer.RenderHtmlAsPdf(htmlContent);
        pdf.SaveAs("registration-form.pdf");
    }
}

How Can Developers Process Image Files and Extract Content?

Modern .NET applications frequently need to convert image files to PDF files or extract images from existing PDF documents. IronPDF supports multiple image formats, including JPEG, PNG, GIF, TIFF, and BMP, enabling users to efficiently create PDF documents from visual content.

using IronPdf;
using System.Collections.Generic;
// Convert multiple image files to a single PDF file
var imageFiles = new List<string> { "page1.png", "page2.jpg", "page3.png" };
PdfDocument pdfFromImages = ImageToPdfConverter.ImageToPdf(imageFiles);
// Extract images from an existing PDF document
PdfDocument existingPdf = PdfDocument.FromFile("report.pdf");
var extractedImages = existingPdf.ExtractAllImages();
foreach (var image in extractedImages)
{
    // Save extracted images to a new directory
    image.SaveAs($"extracted_{Guid.NewGuid()}.png");
}
// Extract text content for text search functionality
string allText = existingPdf.ExtractAllText();
pdfFromImages.SaveAs("combined-images.pdf");

using IronPdf;
using System.Collections.Generic;
// Convert multiple image files to a single PDF file
var imageFiles = new List<string> { "page1.png", "page2.jpg", "page3.png" };
PdfDocument pdfFromImages = ImageToPdfConverter.ImageToPdf(imageFiles);
// Extract images from an existing PDF document
PdfDocument existingPdf = PdfDocument.FromFile("report.pdf");
var extractedImages = existingPdf.ExtractAllImages();
foreach (var image in extractedImages)
{
    // Save extracted images to a new directory
    image.SaveAs($"extracted_{Guid.NewGuid()}.png");
}
// Extract text content for text search functionality
string allText = existingPdf.ExtractAllText();
pdfFromImages.SaveAs("combined-images.pdf");

What Security Features Protect Sensitive Information?

Enterprise PDF files often contain personally identifiable information requiring robust document security. IronPDF enables developers to sign PDFs with digital signatures, encrypt documents with passwords, and permanently redact sensitive information.

using IronPdf;
using IronPdf.Signing;
// Load PDF and apply digital signatures
PdfDocument securePdf = PdfDocument.FromFile("contract.pdf");
// Create signature with certificate
var signature = new PdfSignature("certificate.pfx", "password")
{
    SigningContact = "legal@company.com",
    SigningLocation = "Chicago, IL",
    SigningReason = "Document Approval"
};
// Sign PDFs with cryptographic signature
securePdf.Sign(signature);
// Set document permissions and encryption
securePdf.SecuritySettings.OwnerPassword = "owner123";
securePdf.SecuritySettings.UserPassword = "user456";
securePdf.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.FullPrintRights;
securePdf.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.NoEdit;
// Add custom annotations for review workflows
securePdf.SaveAs("secured-contract.pdf");

using IronPdf;
using IronPdf.Signing;
// Load PDF and apply digital signatures
PdfDocument securePdf = PdfDocument.FromFile("contract.pdf");
// Create signature with certificate
var signature = new PdfSignature("certificate.pfx", "password")
{
    SigningContact = "legal@company.com",
    SigningLocation = "Chicago, IL",
    SigningReason = "Document Approval"
};
// Sign PDFs with cryptographic signature
securePdf.Sign(signature);
// Set document permissions and encryption
securePdf.SecuritySettings.OwnerPassword = "owner123";
securePdf.SecuritySettings.UserPassword = "user456";
securePdf.SecuritySettings.AllowUserPrinting = IronPdf.Security.PdfPrintSecurity.FullPrintRights;
securePdf.SecuritySettings.AllowUserEdits = IronPdf.Security.PdfEditSecurity.NoEdit;
// Add custom annotations for review workflows
securePdf.SaveAs("secured-contract.pdf");

Why Choose a Library Over Traditional PDF SDKs?

IronPDF provides proper cross-platform support across .NET versions from .NET Framework 4.6.2 through .NET 9. Unlike complex PDF SDKs requiring extensive setup, this fully documented library runs identically on Windows, macOS, and Linux with minimal configuration.

Key advantages over traditional .NET SDK approaches:

• Low memory usage optimized for high-volume batch processing
• Native integration with Visual Studio and JetBrains Rider development environments
• Support for all .NET versions, including .NET Standard 2.0, for maximum compatibility
• Office conversion capabilities for DOCX to PDF transformation
• PDF/A compliance for long-term archiving in regulated industries

The library handles PDF forms, including complex XFA forms, supports custom annotations, and enables developers to create PDF files that meet ISO compliant standards for accessibility (PDF/UA) and archival (PDF/A). Whether processing thousands of invoices or generating single-file reports, IronPDF maintains consistent high-quality output with minimal resource consumption.

Start Building with IronPDF

IronPDF transforms complex PDF workflows into simple, maintainable code. From creating PDF documents with form fields to implementing digital signatures and document security, this .NET PDF library provides enterprise-grade capabilities without the complexity of traditional PDF SDKs.

Purchase a license for production deployment, or explore the comprehensive API reference, tutorials, and how-to guides to accelerate your integration.

Get stated with IronPDF now.

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