In this case, the
Barcode Reader for .NET is highly recommended.
Here is a sample code of C# to read qr code :
using BusinessRefinery.Barcode;
using BusinessRefinery.Barcodes.Reader;
BusinessRefinery.Barcode.QRCode barcode = new QRCode();
barcode.Code = "QRCodeReader123";
barcode.Version = QRCodeVersion.V3;
barcode.Rotate = Rotate.Rotate180;
Bitmap bmp = barcode.drawBarcodeOnBitmap();
string[] barcodes = BarCodeReader.scanBarCode(bmp,
BusinessRefinery.Barcodes.Reader.BarCodeType.QRCODE);
Hope it helps!