Biblioteca de código QR em C#

using IronBarCode;
using System.Drawing;

// Reading a barcode is easy with IronBarcode!
var resultFromFile = BarcodeReader.Read(@"file/barcode.png"); // From a file
var resultFromBitMap = BarcodeReader.Read(new Bitmap("barcode.bmp")); // From a bitmap
var resultFromImage = BarcodeReader.Read(Image.FromFile("barcode.jpg")); // From an image file
var resultFromPdf = BarcodeReader.ReadPdf(@"file/mydocument.pdf"); // From PDF use ReadPdf

// To configure and fine-tune barcode reading, utilize the BarcodeReaderOptions class
var myOptionsExample = new BarcodeReaderOptions
{
    // Choose a reading speed from: Faster, Balanced, Detailed, ExtremeDetail
    // There is a tradeoff in performance as more detail is set
    Speed = ReadingSpeed.Balanced,

    // Reader will stop scanning once a single barcode is found (if set to true)
    ExpectMultipleBarcodes = true,

    // By default, all barcode formats are scanned for
    // Specifying a subset of barcode types to search for would improve performance
    ExpectBarcodeTypes = BarcodeEncoding.AllOneDimensional,

    // Utilize multiple threads to read barcodes from multiple images in parallel
    Multithreaded = true,

    // Maximum threads for parallelized barcode reading
    // Default is 4
    MaxParallelThreads = 2,

    // The area of each image frame in which to scan for barcodes
    // Specifying a crop area will significantly improve performance and avoid noisy parts of the image
    CropArea = new Rectangle(),

    // Special setting for Code39 barcodes
    // If a Code39 barcode is detected, try to read with both the base and extended ASCII character sets
    UseCode39ExtendedMode = true
};

// Read with the options applied
var results = BarcodeReader.Read("barcode.png", myOptionsExample);

// Create a barcode with one line of code
var myBarcode = BarcodeWriter.CreateBarcode("12345", BarcodeWriterEncoding.EAN8);

// After creating a barcode, we may choose to resize
myBarcode.ResizeTo(400, 100);

// Save our newly-created barcode as an image
myBarcode.SaveAsImage("EAN8.jpeg");

// Get the barcode as an image for further processing
var myBarcodeImage = myBarcode.Image;

using IronBarCode;
using IronSoftware.Drawing;

// Choose which filters are to be applied (in order)
// Set cacheAtEachIteration = true to save the intermediate image data after each filter is applied
var filtersToApply = new ImageFilterCollection(cacheAtEachIteration: true) {
    new SharpenFilter(),
    new InvertFilter(),
    new ContrastFilter(),
    new BrightnessFilter(),
    new AdaptiveThresholdFilter(),
    new BinaryThresholdFilter(),
    new GaussianBlurFilter(),
    new MedianBlurFilter(),
    new BilateralFilter()
};

BarcodeReaderOptions myOptionsExample = new BarcodeReaderOptions()
{
    // Set chosen filters in BarcodeReaderOptions
    ImageFilters = filtersToApply,

    Speed = ReadingSpeed.Balanced,
    ExpectMultipleBarcodes = true,
};

// Read with the options applied
BarcodeResults results = BarcodeReader.Read("screenshot.png", myOptionsExample);

AnyBitmap[] filteredImages = results.FilterImages();

// Export intermediate image files to disk
for (int i = 0 ; i < filteredImages.Length ; i++)
    filteredImages[i].SaveAs($"{i}_barcode.png");

// Or
results.ExportFilterImagesToDisk("filter-result.jpg");

using IronBarCode;
using System.Drawing;

/*** CREATING BARCODE IMAGES ***/

// Create and save a barcode in a single line of code
BarcodeWriter.CreateBarcode("12345", BarcodeWriterEncoding.EAN8).ResizeTo(400, 100).SaveAsImage("EAN8.jpeg");

/*****  IN-DEPTH BARCODE CREATION OPTIONS *****/

// BarcodeWriter.CreateBarcode creates a GeneratedBarcode which can be styled and exported as an Image object or file
GeneratedBarcode MyBarCode = BarcodeWriter.CreateBarcode("Any Number, String or Binary Value", BarcodeWriterEncoding.Code128);

// Style the Barcode in a fluent LINQ-style fashion
MyBarCode.ResizeTo(300, 150).SetMargins(20).AddAnnotationTextAboveBarcode("Example EAN8 Barcode").AddBarcodeValueTextBelowBarcode();
MyBarCode.ChangeBackgroundColor(Color.LightGoldenrodYellow);

// Save the barcode as an image file
MyBarCode.SaveAsImage("MyBarCode.png");
MyBarCode.SaveAsGif("MyBarCode.gif");
MyBarCode.SaveAsHtmlFile("MyBarCode.html");
MyBarCode.SaveAsJpeg("MyBarCode.jpg");
MyBarCode.SaveAsPdf("MyBarCode.Pdf");
MyBarCode.SaveAsPng("MyBarCode.png");
MyBarCode.SaveAsTiff("MyBarCode.tiff");
MyBarCode.SaveAsWindowsBitmap("MyBarCode.bmp");

// Save the barcode as a .NET native object
Image MyBarCodeImage = MyBarCode.Image;
Bitmap MyBarCodeBitmap = MyBarCode.ToBitmap();

byte[] PngBytes = MyBarCode.ToPngBinaryData();

using (System.IO.Stream PdfStream = MyBarCode.ToPdfStream())
{
    // Stream barcode image output also works for GIF, JPEG, PDF, PNG, BMP and TIFF
}

// Save MyBarCode as an HTML file or tag
MyBarCode.SaveAsHtmlFile("MyBarCode.Html");
string ImgTagForHTML = MyBarCode.ToHtmlTag();
string DataURL = MyBarCode.ToDataUrl();

// Save MyBarCode to a new PDF, or stamp it in any position on any page(s) of an existing document
MyBarCode.SaveAsPdf("MyBarCode.Pdf");
MyBarCode.StampToExistingPdfPage("ExistingPDF.pdf", 200, 50, 1);  // Position (200, 50) on page 1
MyBarCode.StampToExistingPdfPages("ExistingPDF.pdf", 200, 50, new[] { 1, 2, 3 }, "Password123");  // Multiple pages of an encrypted PDF

using IronBarCode;
using System;
using System.Drawing;

/*** STYLING GENERATED BARCODES  ***/

// BarcodeWriter.CreateBarcode creates a GeneratedBarcode object which allows the barcode to be styled and annotated.
GeneratedBarcode MyBarCode = BarcodeWriter.CreateBarcode("Iron Software", BarcodeWriterEncoding.QRCode);

// Any text (or commonly, the value of the barcode) can be added to the image in a default or specified font.
// Text positions are automatically centered, above or below. Fonts that are too large for a given image are automatically scaled down.
MyBarCode.AddBarcodeValueTextBelowBarcode();
MyBarCode.AddAnnotationTextAboveBarcode("This is my barcode");

// Resize, add margins and check final image dimensions
MyBarCode.ResizeTo(300, 300); // Resize in pixels
MyBarCode.SetMargins(0, 20, 0, 20); // Set margins in pixels

int FinalWidth = MyBarCode.Width;
int FinalHeight = MyBarCode.Height;

// Recolor the barcode and its background
MyBarCode.ChangeBackgroundColor(Color.LightGray);
MyBarCode.ChangeBarCodeColor(Color.DarkSlateBlue);
if (!MyBarCode.Verify())
{
    Console.WriteLine("Color contrast should be at least 50% or a barcode may become unreadable. Test using GeneratedBarcode.Verify()");
}

// Finally, save the result
MyBarCode.SaveAsHtmlFile("StyledBarcode.html");

/*** STYLING BARCODES IN A SINGLE LINQ-STYLE EXPRESSION ***/

// Create a barcode in one line of code
BarcodeWriter.CreateBarcode("https://ironsoftware.com", BarcodeWriterEncoding.Aztec).ResizeTo(250, 250).SetMargins(10).AddBarcodeValueTextAboveBarcode().SaveAsImage("StyledBarcode.png");

/*** STYLING QR CODES WITH LOGO IMAGES OR BRANDING ***/

// Use the QRCodeWriter.CreateQrCodeWithLogo Method instead of BarcodeWriter.CreateBarcode
// Logo will automatically be sized appropriately and snapped to the QR grid.

var qrCodeLogo = new QRCodeLogo("ironsoftware_logo.png");
GeneratedBarcode myQRCodeWithLogo = QRCodeWriter.CreateQrCodeWithLogo("https://ironsoftware.com/", qrCodeLogo);
myQRCodeWithLogo.ResizeTo(500, 500).SetMargins(10).ChangeBarCodeColor(Color.DarkGreen);
myQRCodeWithLogo.ResizeTo(500, 500).SetMargins(10).ChangeBarCodeColor(Color.DarkGreen);
myQRCodeWithLogo.SaveAsPng("QRWithLogo.Png").SaveAsPdf("MyVerifiedQR.html"); // Save as 2 different formats

using IronBarCode;

GeneratedBarcode MyBarCode = BarcodeWriter.CreateBarcode("1234567890", BarcodeWriterEncoding.Code128);

// Save as a stand-alone HTML file without any image assets
MyBarCode.SaveAsHtmlFile("MyBarCode.html");

// Save as a stand-alone HTML image tag which can be served in HTML files, ASPX or MVC Views. No image assets required, the tag embeds the entire image in its source content
string ImgTag = MyBarCode.ToHtmlTag();

// Turn the image into a HTML/CSS Data URI.
string DataURI = MyBarCode.ToDataUrl();