How to read barcode from uploaded file for barcode reader API in VB.NET and PDF.co Web API

Learn how to read barcode from uploaded file to have barcode reader API in VB.NET

The documentation is designed to help you to implement the features on your side. Barcode reader API in VB.NET can be implemented with PDF.co Web API. PDF.co Web API is the flexible Web API that includes full set of functions from e-signature requests to data extraction, OCR, images recognition, pdf splitting and pdf splitting. Can also generate barcodes and read barcodes from images, scans and pdf.

VB.NET code snippet like this for PDF.co Web API works best when you need to quickly implement barcode reader API in your VB.NET application. For implimentation of this functionality, please copy and paste code below into your app using code editor. Then compile and run your app. You can use these VB.NET sample examples in one or many applications.

Our website provides free trial version of PDF.co Web API that includes source code samples to help with your VB.NET project.

Try PDF.co Web API today:  60 Day Free Trial (on-premise) or  Web API (on-demand version)

Module1.vb
      
Imports System.IO Imports System.Net Imports Newtonsoft.Json.Linq Module Module1 ' The authentication key (API Key). ' Get your own by registering at https://app.pdf.co/documentation/api Const API_KEY As String = "***********************************" ' Source file name const SourceFile as string = ".\sample.pdf" ' Comma-separated list of barcode types to search. ' See valid barcode types in the documentation https://app.pdf.co/documentation/api/1.0/barcode/read_from_url.html Const BarcodeTypes As String = "Code128,Code39,Interleaved2of5,EAN13" ' Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'. Const Pages As String = "" Sub Main() ' Create standard .NET web client instance Dim webClient As WebClient = New WebClient() ' Set API Key webClient.Headers.Add("x-api-key", API_KEY) ' 1. RETRIEVE THE PRESIGNED URL TO UPLOAD THE FILE. ' * If you already have a direct file URL, skip to the step 3. ' Prepare URL for `Get Presigned URL` API call Dim query As string = Uri.EscapeUriString(string.Format( "https://api.pdf.co/v1/file/upload/get-presigned-url?contenttype=application/octet-stream&name={0}", Path.GetFileName(SourceFile))) Try ' Execute request Dim response As string = webClient.DownloadString(query) ' Parse JSON response Dim json As JObject = JObject.Parse(response) If json("error").ToObject(Of Boolean) = False Then ' Get URL to use for the file upload Dim uploadUrl As string = json("presignedUrl").ToString() ' Get URL of uploaded file to use with later API calls Dim uploadedFileUrl As string = json("url").ToString() ' 2. UPLOAD THE FILE TO CLOUD. webClient.Headers.Add("content-type", "application/octet-stream") webClient.UploadFile(uploadUrl, "PUT", SourceFile) ' You can use UploadData() instead if your file is byte array or Stream ' 3. READ BARCODES FROM UPLOADED FILE ' Prepare URL for `Barcode Reader` API call query = Uri.EscapeUriString(String.Format( "https://api.pdf.co/v1/barcode/read/from/url?types={0}&pages={1}&url={2}", BarcodeTypes, Pages, uploadedFileUrl)) ' Execute request response = webClient.DownloadString(query) ' Parse JSON response json = JObject.Parse(response) If json("error").ToObject(Of Boolean) = False Then ' Display found barcodes in console For Each token As JToken In json("barcodes") Console.WriteLine("Found barcode:") Console.WriteLine(" Type: " + token("TypeName").ToString()) Console.WriteLine(" Value: " + token("Value").ToString()) Console.WriteLine(" Document Page Index: " + token("Page").ToString()) Console.WriteLine(" Rectangle: " + token("Rect").ToString()) Console.WriteLine(" Confidence: " + token("Confidence").ToString()) Console.WriteLine() Next Else Console.WriteLine(json("message").ToString()) End If End If Catch ex As WebException Console.WriteLine(ex.ToString()) End Try webClient.Dispose() Console.WriteLine() Console.WriteLine("Press any key...") Console.ReadKey() End Sub End Module

Try PDF.co Web API today:  60 Day Free Trial (on-premise) or  Web API (on-demand version)

packages.config
      
<?xml version="1.0" encoding="utf-8"?> <packages> <package id="Newtonsoft.Json" version="10.0.3" targetFramework="net40" /> </packages>

Try PDF.co Web API today:  60 Day Free Trial (on-premise) or  Web API (on-demand version)

VIDEO

ON-PREMISE VERSION INFORMATION

Get 60 Day Free Trial or Visit PDF.co Web API Home Page

Explore PDF.co Web API Documentation

Get PDF.co Web API Free Training

WEB API

Get Your Free API Key

Explore Web API Documentation

Related Samples: