How to read barcode from URL asynchronously for barcode reader API in C# with PDF.co Web API

How to read barcode from URL asynchronously for barcode reader API in C#: Step By Step Tutorial

The sample source codes on this page will demonstrate you how to make barcode reader API in C#. Barcode reader API in C# can be implemented with PDF.co Web API. PDF.co Web API is the Rest API that provides set of data extraction functions, tools for documents manipulation, splitting and merging of pdf files. Includes built-in OCR, images recognition, can generate and read barcodes from images, scans and pdf.

The SDK samples like this one below explain how to quickly make your application do barcode reader API in C# with the help of PDF.co Web API. For implimentation of this functionality, please copy and paste code below into your app using code editor. Then compile and run your app. Test C# sample code examples whether they respond your needs and requirements for the project.

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

On-demand (REST Web API) version:
 Web API (on-demand version)

On-premise offline SDK for Windows:
 60 Day Free Trial (on-premise)

ByteScoutWebApiExample.csproj

      
<?xml version="1.0" encoding="utf-8"?> <Project ToolsVersion="12.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003"> <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" /> <PropertyGroup> <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration> <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform> <ProjectGuid>{1E1C2C34-017E-4605-AE2B-55EA3313BE51}</ProjectGuid> <OutputType>Exe</OutputType> <AppDesignerFolder>Properties</AppDesignerFolder> <RootNamespace>ByteScoutWebApiExample</RootNamespace> <AssemblyName>ByteScoutWebApiExample</AssemblyName> <TargetFrameworkVersion>v4.0</TargetFrameworkVersion> <FileAlignment>512</FileAlignment> </PropertyGroup> <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' "> <PlatformTarget>AnyCPU</PlatformTarget> <DebugSymbols>true</DebugSymbols> <DebugType>full</DebugType> <Optimize>false</Optimize> <OutputPath>bin\Debug\</OutputPath> <DefineConstants>DEBUG;TRACE</DefineConstants> <ErrorReport>prompt</ErrorReport> <WarningLevel>4</WarningLevel> </PropertyGroup> <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' "> <PlatformTarget>AnyCPU</PlatformTarget> <DebugType>pdbonly</DebugType> <Optimize>true</Optimize> <OutputPath>bin\Release\</OutputPath> <DefineConstants>TRACE</DefineConstants> <ErrorReport>prompt</ErrorReport> <WarningLevel>4</WarningLevel> </PropertyGroup> <ItemGroup> <Reference Include="Newtonsoft.Json, Version=10.0.0.0, Culture=neutral, PublicKeyToken=30ad4fe6b2a6aeed, processorArchitecture=MSIL"> <HintPath>packages\Newtonsoft.Json.10.0.3\lib\net40\Newtonsoft.Json.dll</HintPath> <Private>True</Private> </Reference> <Reference Include="System" /> <Reference Include="System.Core" /> <Reference Include="System.Xml.Linq" /> <Reference Include="System.Data" /> <Reference Include="System.Xml" /> </ItemGroup> <ItemGroup> <Compile Include="Program.cs" /> <Compile Include="Properties\AssemblyInfo.cs" /> </ItemGroup> <ItemGroup> <None Include="packages.config" /> </ItemGroup> <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" /> <!-- To modify your build process, add your task inside one of the targets below and uncomment it. Other similar extension points exist, see Microsoft.Common.targets. <Target Name="BeforeBuild"> </Target> <Target Name="AfterBuild"> </Target> --> </Project>

ByteScoutWebApiExample.sln

      
Microsoft Visual Studio Solution File, Format Version 12.00 # Visual Studio 2013 VisualStudioVersion = 12.0.40629.0 MinimumVisualStudioVersion = 10.0.40219.1 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "ByteScoutWebApiExample", "ByteScoutWebApiExample.csproj", "{1E1C2C34-017E-4605-AE2B-55EA3313BE51}" EndProject Global GlobalSection(SolutionConfigurationPlatforms) = preSolution Debug|Any CPU = Debug|Any CPU Release|Any CPU = Release|Any CPU EndGlobalSection GlobalSection(ProjectConfigurationPlatforms) = postSolution {1E1C2C34-017E-4605-AE2B-55EA3313BE51}.Debug|Any CPU.ActiveCfg = Debug|Any CPU {1E1C2C34-017E-4605-AE2B-55EA3313BE51}.Debug|Any CPU.Build.0 = Debug|Any CPU {1E1C2C34-017E-4605-AE2B-55EA3313BE51}.Release|Any CPU.ActiveCfg = Release|Any CPU {1E1C2C34-017E-4605-AE2B-55EA3313BE51}.Release|Any CPU.Build.0 = Release|Any CPU EndGlobalSection GlobalSection(SolutionProperties) = preSolution HideSolutionNode = FALSE EndGlobalSection EndGlobal

Program.cs

      
using System; using System.Collections.Generic; using System.IO; using System.Net; using System.Threading; using System.Threading.Tasks; using Newtonsoft.Json; using Newtonsoft.Json.Linq; // Cloud API asynchronous "Barcode Reader" job example. // Allows to avoid timeout errors when processing huge or scanned PDF documents. namespace ByteScoutWebApiExample { class Program { // The authentication key (API Key). // Get your own by registering at https://app.pdf.co/documentation/api const String API_KEY = "***********************************"; // Direct URL of source file (image or PDF) to search barcodes in. const string SourceFileURL = "https://bytescout-com.s3.amazonaws.com/files/demo-files/cloud-api/barcode-reader/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 string BarcodeTypes = "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 string Pages = ""; // (!) Make asynchronous job const bool Async = true; static void Main(string[] args) { // Create standard .NET web client instance WebClient webClient = new WebClient(); // Set API Key webClient.Headers.Add("x-api-key", API_KEY); // Prepare requests params as JSON // See documentation: https://apidocs.pdf.co/?#barcode-reader Dictionary<string, string> parameters = new Dictionary<string, string>(); parameters.Add("url", SourceFileURL); parameters.Add("type", BarcodeTypes); parameters.Add("pages", Pages); parameters.Add("async", Async.ToString()); // Convert dictionary of params to JSON string jsonPayload = JsonConvert.SerializeObject(parameters); try { // URL of "Barcode Reader" endpoint string url = "https://api.pdf.co/v1/barcode/read/from/url"; // Execute POST request with JSON payload string response = webClient.UploadString(url, jsonPayload); // Parse JSON response JObject json = JObject.Parse(response); if (json["error"].ToObject<bool>() == false) { // Asynchronous job ID string jobId = json["jobId"].ToString(); // URL of generated JSON file with decoded barcodes that will available after the job completion string resultFileUrl = json["url"].ToString(); // Check the job status in a loop. // If you don't want to pause the main thread you can rework the code // to use a separate thread for the status checking and completion. do { string status = CheckJobStatus(jobId); // Possible statuses: "working", "failed", "aborted", "success". // Display timestamp and status (for demo purposes) Console.WriteLine(DateTime.Now.ToLongTimeString() + ": " + status); if (status == "success") { // Download JSON results file as string string jsonFileString = webClient.DownloadString(resultFileUrl); JArray jsonFoundBarcodes = JArray.Parse(jsonFileString); // Display found barcodes in console foreach (JToken token in jsonFoundBarcodes) { Console.WriteLine("Found barcode:"); Console.WriteLine(" Type: " + token["TypeName"]); Console.WriteLine(" Value: " + token["Value"]); Console.WriteLine(" Document Page Index: " + token["Page"]); Console.WriteLine(" Rectangle: " + token["Rect"]); Console.WriteLine(" Confidence: " + token["Confidence"]); Console.WriteLine(); } break; } else if (status == "working") { // Pause for a few seconds Thread.Sleep(3000); } else { Console.WriteLine(status); break; } } while (true); } else { // Display service reported error Console.WriteLine(json["message"].ToString()); } } catch (WebException e) { // Display request error Console.WriteLine(e.ToString()); } finally { webClient.Dispose(); } Console.WriteLine(); Console.WriteLine("Press any key..."); Console.ReadKey(); } static string CheckJobStatus(string jobId) { using (WebClient webClient = new WebClient()) { // Set API Key webClient.Headers.Add("x-api-key", API_KEY); string url = "https://api.pdf.co/v1/job/check?jobid=" + jobId; string response = webClient.DownloadString(url); JObject json = JObject.Parse(response); return Convert.ToString(json["status"]); } } } }

packages.config

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

VIDEO

ON-PREMISE OFFLINE SDK

Get 60 Day Free Trial

See also:

ON-DEMAND REST WEB API

Get Your API Key

See also:

Related Samples: