Table of Contents

QR Code Generator for .NET

Open-source library for generating QR codes from text strings and byte arrays.

.NET API Documentation

Additional information on GitHub project page

Features

Core features:

  • Supports encoding all 40 versions (sizes) and all 4 error correction levels, as per the QR Code Model 2 standard
  • Output formats: Raw modules/pixels of the QR symbol, SVG, XAML path, PNG and BMP files. For other raster bitmap formats, see project home page.
  • Computes optimal segment modes for smallest possible QR code.
  • High speed: 10x faster than comparable libraries
  • Open source code under the permissive MIT License
  • Built for .NET Standard 2.0 and therefore runs on most modern .NET platforms (.NET Core, .NET Framework, Mono etc.).
  • Available as a NuGet package (named Net.Codecrete.QrCodeGenerator)
  • Example code for WinForms, WPF, ASP.NET, ImageSharp, SkiaSharp and many more

Advanced features:

  • Specify minimum and maximum version number allowed
  • Specify text encoding and use of ECI designators
  • Create data segments manually
  • Split long text into multiple linked QR codes (aka Structured Append)

Examples

Simple operation:

using System.IO;
using System.Text;
using Net.Codecrete.QrCodeGenerator;

namespace Examples
{
    class SimpleOperation
    {
        static void Main()
        {
            var qr = QrCode.EncodeText("Hello, world!", QrCode.Ecc.Medium);
            string svg = qr.ToSvgString(4);
            File.WriteAllText("hello-world-qr.svg", svg, Encoding.UTF8);
        }
    }
}

Manual operation:

using Net.Codecrete.QrCodeGenerator;

namespace Examples
{
    class ManualOperation
    {
        static void Main()
        {
            var qrCode = QrCode.EncodeTextAdvanced("3141592653589793238462643383",
                QrCode.Ecc.High, eci: ECI.Latin9, minVersion: 5, maxVersion: 5);
            foreach (var rect in qrCode.ToRectangles())
            {
                ... paint rectangle rect.X, rect.Y, rect.Width, rect.Height
            }
        }
    }
}

Requirements

QR Code Generator for .NET requires a .NET implementation compatible with .NET Standard 2.0 or higher, i.e. any of:

  • .NET Core 2.0 or higher
  • .NET Framework 4.6.1 or higher
  • Mono 5.4 or higher
  • Universal Windows Platform 10.0.16299 or higher
  • Xamarin

Raster Images / Bitmaps

Starting with .NET 6, System.Drawing is only supported on Windows operating system and thus cannot be used for multi-platform libraries like this one. Therefore, ToBitmap() has been removed.

Two raster bitmap formats are supported with the need for additional libraries:

These methods are limited, e.g. with regards to the size of the generated image. For more advanced and more efficient ways to generate different raster image formats:

  • Select one of the imaging libraries below
  • Add the NuGet dependencies to your project
  • Copy the appropriate QrCodeBitmapExtensions.cs file to your project
Library Recommendation NuGet dependencies Extension file
System.Drawing For Windows only projects System.Drawing.Common QrCodeBitmapExtensions.cs
SkiaSharp For macOS, Linux, iOS, Android and multi-platform projects SkiaSharp and SkiaSharp.NativeAssets.Linux (for Linux only) QrCodeBitmapExtensions.cs
ImageSharp Alternative for multi-platform projects. Might require a commercial license. SixLabors.ImageSharp.Drawing QrCodeBitmapExtensions.cs

Using these extension methods, generating PNG images is straight-forward:

using Net.Codecrete.QrCodeGenerator;

namespace Examples
{
    class PngImage
    {
        static void Main()
        {
            var qr = QrCode.EncodeText("Hello, world!", QrCode.Ecc.Medium);
            qr.SaveAsPng("hello-world-qr.png", 10, 3);
        }
    }
}
Edit this page