PDF.co Web API - PDF To Image API - C# - Convert PDF To JPEG From URL Asynchronously

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PDF-co-Web-API-C-sharp-Convert-PDF-To-JPEG-From-URL-Asynchronously.pdf

How to convert PDF to JPEG from URL asynchronously for PDF to image API in C# using PDF.co Web API

See how to convert PDF to JPEG from URL asynchronously to have PDF to image API in C#

The documentation is designed to help you to implement the features on your side. PDF.co Web API was made to help with PDF to image API in C#. PDF.co Web API is the Web API with a set of tools for documents manipulation, data conversion, data extraction, splitting and merging of documents. Includes image recognition, built-in OCR, barcode generation and barcode decoders to decode bar codes from scans, pictures and pdf.

You will save a lot of time on writing and testing code as you may just take the code below and use it in your application. This C# sample code should be copied and pasted into your project. After doing this just compile your project and click Run. Further enhancement of the code will make it more vigorous.

PDF.co Web API – free trial version is on available our website. Also, there are other code samples to help you with your C# application included into trial version.

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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 Newtonsoft.Json;
using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.Net;
using System.Threading;


// Cloud API asynchronous "PDF To JPEG" 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 = "***********************************";
		
		// Source PDF file
		const string SourceFileUrl = @"https://bytescout-com.s3.amazonaws.com/files/demo-files/cloud-api/pdf-to-image/sample.pdf";
		// Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'.
		const string Pages = "";
		// PDF document password. Leave empty for unprotected documents.
		const string Password = "";
		// (!) 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);

			try
			{
				// URL for `PDF To JPEG` API call
				string url = "https://api.pdf.co/v1/pdf/convert/to/jpg";

				// Prepare requests params as JSON
				Dictionary<string, object> parameters = new Dictionary<string, object>();
				parameters.Add("password", Password);
				parameters.Add("pages", Pages);
				parameters.Add("url", SourceFileUrl);
				parameters.Add("async", Async);

				// Convert dictionary of params to JSON
				string jsonPayload = JsonConvert.SerializeObject(parameters);

				// 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 available after the job completion; it will contain URLs of result JPEG files.
					string resultJsonFileUrl = 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 file as string
							string jsonFileString = webClient.DownloadString(resultJsonFileUrl);

							JArray resultFilesUrls = JArray.Parse(jsonFileString);

							// Download generated JPEG files
							int page = 1;
							foreach (JToken token in resultFilesUrls)
							{
								string resultFileUrl = token.ToString();
								string localFileName = String.Format(@".\page{0}.jpg", page);

								webClient.DownloadFile(resultFileUrl, localFileName);

								Console.WriteLine("Downloaded \"{0}\".", localFileName);
								page++;
							}
							break;
						}
						else if (status == "working")
						{
							// Pause for a few seconds
							Thread.Sleep(3000);
						}
						else
						{
							Console.WriteLine(status);
							break;
						}
					}
					while (true);
				}
				else
				{
					Console.WriteLine(json["message"].ToString());
				}
			}
			catch (WebException e)
			{
				Console.WriteLine(e.ToString());
			}

			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>

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printable version:
PDF-co-Web-API-C-sharp-Convert-PDF-To-JPEG-From-URL-Asynchronously.pdf