Create a blank ASP.NET Core Web application.

Server side: Add references to the nuget-packages to ASP.NET Core Web application.

Server side: Add Web API controller that allows to recognizes barcodes in image.

• Press the right mouse button on the "Controllers" folder and select the "Add => Controller..." menu from context menu
  
• Select Empty API controller template, set the controller name to the "MyVintasoftBarcodeApiController" and press the "Add" button
  
• Specify that MyVintasoftBarcodeApiController class is derived from Vintasoft.Barcode.AspNetCore.ApiControllers.VintasoftBarcodeApiController class
  
  Here are source codes of MyVintasoftBarcodeApiController class:
  
  • C#

  using Vintasoft.Barcode.AspNetCore.ApiControllers;
  
  namespace WebApplication1.Controllers
  {
      public class MyVintasoftBarcodeApiController : VintasoftBarcodeApiController
      {
  
          public MyVintasoftBarcodeApiController(IWebHostEnvironment hostingEnvironment)
              : base(hostingEnvironment)
          {
          }
  
      }
  }
  

  
  

Server side: Add reference to the nuget-package "Microsoft.AspNetCore.Mvc.NewtonsoftJson" for deserialization of barcode recognition results.

• Add reference to the nuget-package Microsoft.AspNetCore.Mvc.NewtonsoftJson to the ASP.NET Core project:
  
• Open the "Program.cs" file and add code line "builder.Services.AddControllersWithViews().AddNewtonsoftJson();". This is necessary for correct deserialization of barcode recognition results.
  
  Here are source codes of Program.cs:
  
  • C#

  var builder = WebApplication.CreateBuilder(args);
  
  // Add services to the container.
  builder.Services.AddControllersWithViews().AddNewtonsoftJson();
  
  var app = builder.Build();
  
  // Configure the HTTP request pipeline.
  if (!app.Environment.IsDevelopment())
  {
      app.UseExceptionHandler("/Home/Error");
      // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
      app.UseHsts();
  }
  
  app.UseHttpsRedirection();
  app.UseRouting();
  
  app.UseAuthorization();
  
  app.MapStaticAssets();
  
  app.MapControllerRoute(
      name: "default",
      pattern: "{controller=Home}/{action=Index}/{id?}")
      .WithStaticAssets();
  
  
  app.Run();
  
  

  
  

Client side: Add Vintasoft JavaScript files to the project.

• Add the "wwwroot\lib\Vintasoft" folder to ASP.NET Core application.
  
  
• Copy JavaScript-file "Vintasoft.Shared.js" from Github into "wwwroot\lib\Vintasoft\" folder.
  Copy JavaScript-file "Vintasoft.Barcode.js" from Github into "wwwroot\lib\Vintasoft\" folder.
  

Client side: Add JavaScript code, which recognizes barcodes in image and displays barcode recognition result, to the web view.

• Create folder "wwwroot\UploadedImageFiles\SessionID" and copy PNG-image file with barcodes from Github to the folder. We will recognize barcodes in this image.
  
  
• Open file "Views\Home\Index.cshtml", clear the file, add HTML code (references to VintaSoft JavaScript files; DIV-element that will display information about recognized barcodes) to the "Index.cshtml" file:
  
  Here is HTML code of "Index.cshtml" file:
  
  • HTML

  <script src="~/lib/Vintasoft/Vintasoft.Shared.js" type="text/javascript"></script>
  <script src="~/lib/Vintasoft/Vintasoft.Barcode.js" type="text/javascript"></script>
  
  <div id="barcodeInformation"></div>
  
  

  
  
• Open file "wwwroot\js\site.js", clear the file, add JavaScript code (recognizes barcode in image and displays barcode recognition result) to the "site.js" file:
  
  Here is JavaScript code that recognizes barcodes in image and displays barcode recognition result:
  
  • JavaScript

  /**
   * Recognizes barcodes.
   */
  function __recognizeBarcodes() {
      // set the session identifier
      Vintasoft.Shared.WebImagingEnviromentJS.set_SessionId("SessionID");
  
      // create service that allows to recognize barcodes
      var barcodeService = new Vintasoft.Shared.WebServiceControllerJS("vintasoft/api/MyVintasoftBarcodeApi");
  
      // create the barcode reader
      var barcodeReader = new Vintasoft.Barcode.WebBarcodeReaderJS(barcodeService);
      // specify that Code39 barcode must be searched
      barcodeReader.get_Settings().set_BarcodeType(new Vintasoft.Barcode.WebBarcodeTypeEnumJS("Code39"));
  
      // create web image that references to a file "AllSupportedBarcodes.png" in directory "/UploadedImageFiles/SessionID/"
      var imageSource = new Vintasoft.Shared.WebImageSourceJS("AllSupportedBarcodes.png");
      var image = new Vintasoft.Shared.WebImageJS(imageSource, 0);
  
      // send an asynchronous request for barcode recognition
      barcodeReader.readBarcodes(image, __recognizeBarcodes_success, __recognizeBarcodes_fail);
  }
  
  /**
   * Barcodes are recognized successfully.
   */
  function __recognizeBarcodes_success(data) {
      if (data.success) {
          // get the barcode recognition result
          var barcodeRecognitionResults = data.results;
  
          var htmlMarkup = '';
          // if no barcodes found
          if (barcodeRecognitionResults.length == 0) {
              htmlMarkup = 'No barcodes found.';
          }
          // if barcodes are found
          else {
              htmlMarkup = barcodeRecognitionResults.length.toString() + ' barcodes are found.<br />';
              htmlMarkup += '<br />';
  
              // for each recognized barcode
              for (var i = 0; i < barcodeRecognitionResults.length; i++) {
                  // get the barcode recognition result
                  var barcodeRecognitionResult = barcodeRecognitionResults[i];
  
                  // output information about recognized barcode
                  htmlMarkup += '[' + (i + 1) + ':' + barcodeRecognitionResult.barcodeType + ']<br />';
                  htmlMarkup += '  Value: ' + barcodeRecognitionResult.value + '<br />';
                  htmlMarkup += '  Confidence: ' + barcodeRecognitionResult.confidence + '<br />';
                  htmlMarkup += '  Reading quality: ' + barcodeRecognitionResult.readingQuality.toFixed(2) + '<br />';
                  htmlMarkup += '  Threshold: ' + barcodeRecognitionResult.threshold + '<br />';
                  htmlMarkup += '  Region: ' +
                      'LT=(' + barcodeRecognitionResult.region.leftTop.x + ',' + barcodeRecognitionResult.region.leftTop.y + '); ' +
                      'RT=(' + barcodeRecognitionResult.region.rightTop.x + ',' + barcodeRecognitionResult.region.rightTop.y + '); ' +
                      'LB=(' + barcodeRecognitionResult.region.leftBottom.x + ',' + barcodeRecognitionResult.region.leftBottom.y + '); ' +
                      'RB=(' + barcodeRecognitionResult.region.rightBottom.x + ',' + barcodeRecognitionResult.region.rightBottom.y + '); ' +
                      'Angle=' + barcodeRecognitionResult.region.angle.toFixed(1) + '°<br />';
  
                  htmlMarkup += '<br />';
              }
          }
  
          var barcodeInformationElement = document.getElementById("barcodeInformation");
          barcodeInformationElement.innerHTML = htmlMarkup;
      }
  }
  
  /**
   * Barcode recognition is failed.
   */
  function __recognizeBarcodes_fail(data) {
      // show information about error
      alert(data.errorMessage);
  }
  
  
  // recognize barcodes
  __recognizeBarcodes();
  
  

  
  

Run the ASP.NET Core application and see the result.