This C# demo code will read all QR Codes in image file "qrcode-aspnet.gif" and return all the barcode data strings.
Recognize ASP.NET Web Project QR Code Barcodes in VB.NET
You can use the following one line VB.NET demo code to read and decode all your ASP.NET project QR Code barcodes from a image file.
Dim datas() AsString = BarcodeReader.read("c:/qrcode-aspnet.gif", BarcodeReader.QRCODE)
The above VB.NET demo code will decode all QR Code barcodes in image file "qrcode-aspnet.gif" and return all the barcode data strings.
Improve ASP.NET QR Code 2D Barcode Scanning Effect
The following settings are needed for reading ASP.NET QR Code barcodes from a large size image file (like 4mb per image).
Read maximum one QR Code barcode: Please set "maxOneBarcodePerPage" to true if there is maximum one QR Code per image, per page in tiff or pdf document.
If this property is true, the process of QR Code recognition will be stopped when our ASP.NET Barcode Reader Library detects one QR Code barcode.
If this property is false (default value), our ASP.NET Barcode Reader Library will use total 5 algorithms and each will read the whole image from 4 directions.
Scan the partial image instead of the whole file: If the QR Code is always appears at a specific area in the image file, you can customize our ASP.NET Barcode Reader Library to read that area only. This will help to reduce lots of reading time, CPU and memory usage.
To do so, please specify the left top point and right bottom point of the area (the point X, Y values are expressed in percentage of the whole image, so image most left top point is (0%, 0%), and most right bottom point is (100%, 100%)). And we provide the following free C# & VB.NET codes to achieve this.
Free C# Sample Code for ASP.NET QR Code Recognition:
OptimizeSetting setting = new OptimizeSetting();
setting.setMaxOneBarcodePerPage(true);
ScanArea top20 = new ScanArea(new PointF(0.0F, 0.0F), new PointF(100.0F, 20.0F));
ScanArea bottom20 = new ScanArea(new PointF(0.0F, 80.0F), new PointF(100.0F, 100.0F));
List<ScanArea> areas = new List<ScanArea>(); areas.Add(top20); areas.Add(bottom20);