PDF to text API in VB.NET and PDF.co Web API
PDF to text API in VB.NET
The documentation is crafted to assist you to apply the features on your side easily. PDF.co Web API helps with PDF to text API in VB.NET. 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.
If you want to quickly learn then these fast application programming interfaces of PDF.co Web API for VB.NET plus the guideline and the VB.NET code below will help you quickly learn PDF to text API. If you want to know how it works, then this VB.NET sample code should be copied and pasted into your application’s code editor. Then just compile and run it. Further improvement of the code will make it more robust.
Trial version can be downloaded from our website for free. It contains this and other source code samples for VB.NET.
On-demand (REST Web API) version:
Web API (on-demand version)
On-premise offline SDK for Windows:
60 Day Free Trial (on-premise)
ByteScoutWebApiExample.sln
Microsoft Visual Studio Solution File, Format Version 12.00 # Visual Studio 15 VisualStudioVersion = 15.0.26730.10 MinimumVisualStudioVersion = 10.0.40219.1 Project("{F184B08F-C81C-45F6-A57F-5ABD9991F28F}") = "ByteScoutWebApiExample", "ByteScoutWebApiExample.vbproj", "{9B91124C-66C3-4BD9-B29E-168C1ABB15AC}" EndProject Global GlobalSection(SolutionConfigurationPlatforms) = preSolution Debug|Any CPU = Debug|Any CPU Release|Any CPU = Release|Any CPU EndGlobalSection GlobalSection(ProjectConfigurationPlatforms) = postSolution {9B91124C-66C3-4BD9-B29E-168C1ABB15AC}.Debug|Any CPU.ActiveCfg = Debug|Any CPU {9B91124C-66C3-4BD9-B29E-168C1ABB15AC}.Debug|Any CPU.Build.0 = Debug|Any CPU {9B91124C-66C3-4BD9-B29E-168C1ABB15AC}.Release|Any CPU.ActiveCfg = Release|Any CPU {9B91124C-66C3-4BD9-B29E-168C1ABB15AC}.Release|Any CPU.Build.0 = Release|Any CPU EndGlobalSection GlobalSection(SolutionProperties) = preSolution HideSolutionNode = FALSE EndGlobalSection GlobalSection(ExtensibilityGlobals) = postSolution SolutionGuid = {4576C9BB-A42D-46A8-9198-7E2982E122FA} EndGlobalSection EndGlobal
ByteScoutWebApiExample.vbproj
<?xml version="1.0" encoding="utf-8"?> <Project ToolsVersion="15.0" 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>{9B91124C-66C3-4BD9-B29E-168C1ABB15AC}</ProjectGuid> <OutputType>Exe</OutputType> <StartupObject>ByteScoutWebApiExample.Module1</StartupObject> <RootNamespace>ByteScoutWebApiExample</RootNamespace> <AssemblyName>ByteScoutWebApiExample</AssemblyName> <FileAlignment>512</FileAlignment> <MyType>Console</MyType> <TargetFrameworkVersion>v4.0</TargetFrameworkVersion> </PropertyGroup> <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' "> <PlatformTarget>AnyCPU</PlatformTarget> <DebugSymbols>true</DebugSymbols> <DebugType>full</DebugType> <DefineDebug>true</DefineDebug> <DefineTrace>true</DefineTrace> <OutputPath>bin\Debug\</OutputPath> <DocumentationFile>ByteScoutWebApiExample.xml</DocumentationFile> <NoWarn>42016,41999,42017,42018,42019,42032,42036,42020,42021,42022</NoWarn> </PropertyGroup> <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' "> <PlatformTarget>AnyCPU</PlatformTarget> <DebugType>pdbonly</DebugType> <DefineDebug>false</DefineDebug> <DefineTrace>true</DefineTrace> <Optimize>true</Optimize> <OutputPath>bin\Release\</OutputPath> <DocumentationFile>ByteScoutWebApiExample.xml</DocumentationFile> <NoWarn>42016,41999,42017,42018,42019,42032,42036,42020,42021,42022</NoWarn> </PropertyGroup> <PropertyGroup> <OptionExplicit>On</OptionExplicit> </PropertyGroup> <PropertyGroup> <OptionCompare>Binary</OptionCompare> </PropertyGroup> <PropertyGroup> <OptionStrict>Off</OptionStrict> </PropertyGroup> <PropertyGroup> <OptionInfer>On</OptionInfer> </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> </Reference> <Reference Include="System" /> <Reference Include="System.Data" /> <Reference Include="System.Deployment" /> <Reference Include="System.Xml" /> <Reference Include="System.Core" /> <Reference Include="System.Xml.Linq" /> <Reference Include="System.Data.DataSetExtensions" /> </ItemGroup> <ItemGroup> <Import Include="Microsoft.VisualBasic" /> <Import Include="System" /> <Import Include="System.Collections" /> <Import Include="System.Collections.Generic" /> <Import Include="System.Data" /> <Import Include="System.Diagnostics" /> <Import Include="System.Linq" /> <Import Include="System.Xml.Linq" /> </ItemGroup> <ItemGroup> <Compile Include="Module1.vb" /> <Compile Include="My Project\AssemblyInfo.vb" /> <Compile Include="My Project\Application.Designer.vb"> <AutoGen>True</AutoGen> <DependentUpon>Application.myapp</DependentUpon> </Compile> <Compile Include="My Project\Resources.Designer.vb"> <AutoGen>True</AutoGen> <DesignTime>True</DesignTime> <DependentUpon>Resources.resx</DependentUpon> </Compile> <Compile Include="My Project\Settings.Designer.vb"> <AutoGen>True</AutoGen> <DependentUpon>Settings.settings</DependentUpon> <DesignTimeSharedInput>True</DesignTimeSharedInput> </Compile> </ItemGroup> <ItemGroup> <EmbeddedResource Include="My Project\Resources.resx"> <Generator>VbMyResourcesResXFileCodeGenerator</Generator> <LastGenOutput>Resources.Designer.vb</LastGenOutput> <CustomToolNamespace>My.Resources</CustomToolNamespace> <SubType>Designer</SubType> </EmbeddedResource> </ItemGroup> <ItemGroup> <None Include="My Project\Application.myapp"> <Generator>MyApplicationCodeGenerator</Generator> <LastGenOutput>Application.Designer.vb</LastGenOutput> </None> <None Include="My Project\Settings.settings"> <Generator>SettingsSingleFileGenerator</Generator> <CustomToolNamespace>My</CustomToolNamespace> <LastGenOutput>Settings.Designer.vb</LastGenOutput> </None> <None Include="packages.config" /> <Content Include="sample-rotated.pdf"> <CopyToOutputDirectory>Always</CopyToOutputDirectory> </Content> <Content Include="profile.json"> <CopyToOutputDirectory>Always</CopyToOutputDirectory> </Content> </ItemGroup> <Import Project="$(MSBuildToolsPath)\Microsoft.VisualBasic.targets" /> </Project>
Module1.vb
Imports System.IO Imports System.Net Imports Newtonsoft.Json 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 PDF file Const SourceFile As String = ".\sample-rotated.pdf" ' Comma-separated list of page indices (or ranges) to process. Leave empty for all pages. Example: '0,2-5,7-'. Const Pages As String = "" ' PDF document password. Leave empty for unprotected documents. Const Password As String = "" ' Destination TXT file name Const DestinationFile As String = ".\result.txt" ' Some of advanced options available through profiles: ' (JSON can be single/double-quoted and contain comments.) ' { ' "profiles": [ ' { ' "profile1": { ' "ExtractInvisibleText": true, // Invisible text extraction. Values: true / false ' "ExtractShadowLikeText": true, // Shadow-like text extraction. Values: true / false ' "ExtractAnnotations": true, // Whether to extract PDF annotations. ' "CheckPermissions": true, // Ignore document permissions. Values: true / false ' "DetectNewColumnBySpacesRatio": 1.2, // A ratio affecting number of spaces between words. ' } ' } ' ] ' } ' Sample profile that sets advanced conversion options. ' Advanced options are properties of CSVExtractor class from ByteScout PDF Extractor SDK used in the back-end: ' https://cdn.bytescout.com/help/BytescoutPDFExtractorSDK/html/87ce5fa6-3143-167d-abbd-bc7b5e160fe5.htm 'Valid RotationAngle values '0 - no rotation '1 - 90 degrees '2 - 180 degrees '3 - 270 degrees ReadOnly Profiles As String = File.ReadAllText("profile.json") 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 ' Set JSON content type webClient.Headers.Add("Content-Type", "application/json") ' 3. CONVERT UPLOADED PDF FILE TO TXT ' Prepare URL for `PDF To TXT` API call Dim url As String = "https://api.pdf.co/v1/pdf/convert/to/text" ' Prepare requests params as JSON ' See documentation: https : //apidocs.pdf.co Dim parameters As New Dictionary(Of String, Object) parameters.Add("name", Path.GetFileName(DestinationFile)) parameters.Add("password", Password) parameters.Add("pages", Pages) parameters.Add("url", uploadedFileUrl) parameters.Add("profiles", Profiles) ' Convert dictionary of params to JSON Dim jsonPayload As String = JsonConvert.SerializeObject(parameters) ' Execute POST request with JSON payload response = webClient.UploadString(url, jsonPayload) ' Parse JSON response json = JObject.Parse(response) If json("error").ToObject(Of Boolean) = False Then ' Get URL of generated TXT file Dim resultFileUrl As String = json("url").ToString() ' Download TXT file webClient.DownloadFile(resultFileUrl, DestinationFile) Console.WriteLine("Generated TXT file saved as ""{0}"" file.", DestinationFile) 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
packages.config
<?xml version="1.0" encoding="utf-8"?> <packages> <package id="Newtonsoft.Json" version="10.0.3" targetFramework="net40" /> </packages>
profile.json
{ "profiles": [ { "profile1": { "RotationAngle": 1 } } ] }
VIDEO
ON-PREMISE OFFLINE SDK
See also:
ON-DEMAND REST WEB API
Get Your API Key
See also:
PDF-co-Web-API-VB-NET-Advanced-Conversion-Options-With-Rotated-Input.pdf