How to extract line items from tables on multiple pages for document parser API in VB.NET with PDF.co Web API

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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" /> </ItemGroup> <ItemGroup> <None Include="packages.config" /> <None Include="MultiPageTable.pdf"> <CopyToOutputDirectory>Always</CopyToOutputDirectory> </None> <None Include="MultiPageTable-template1.yml"> <CopyToOutputDirectory>Always</CopyToOutputDirectory> </None> <None Include="MultiPageTable-template2.yml"> <CopyToOutputDirectory>Always</CopyToOutputDirectory> </None> </ItemGroup> <Import Project="$(MSBuildToolsPath)\Microsoft.VisualBasic.targets" /> </Project>

Module1.vb

      
Imports System.Collections.Specialized Imports System.IO Imports System.Net Imports System.Text Imports System.Threading 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 = ".\MultiPageTable.pdf" ' PDF document password. Leave empty for unprotected documents. Const Password As String = "" ' Destination TXT file name Const DestinationFile As String = ".\result.json" ' (!) Make asynchronous job Const Async As Boolean = True Sub Main() ' Template text. Use Document Parser SDK (https//bytescout.com/products/developer/documentparsersdk/index.html) ' to create templates. ' Read template from file Dim templateText As String = File.ReadAllText("MultiPageTable-template1.yml") ' Dim templateText As String = File.ReadAllText("MultiPageTable-template2.yml") ' 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. PARSE UPLOADED PDF DOCUMENT ' URL for `Document Parser` API call query = Uri.EscapeUriString( String.Format("https://api.pdf.co/v1/pdf/documentparser?url={0}&async={1}", uploadedFileUrl, Async) ) Dim requestBody As New NameValueCollection() requestBody.Add("template", templateText) ' Execute request Dim responseBytes As Byte() = webClient.UploadValues(query, "POST", requestBody) response = Encoding.UTF8.GetString(responseBytes) ' Parse JSON response json = JObject.Parse(response) If json("error").ToObject(Of Boolean) = False Then ' Asynchronous job ID Dim jobId As String = json("jobId").ToString() ' URL of generated PDF file that will available after the job completion Dim resultFileUrl As String = 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 Dim status As String = CheckJobStatus(jobId) ' Possible statuses: "working", "failed", "aborted", "success". ' Display timestamp and status (for demo purposes) Console.WriteLine(DateTime.Now.ToLongTimeString() + ": " + status) If status = "success" Then ' Download PDF file webClient.DownloadFile(resultFileUrl, DestinationFile) Console.WriteLine("Generated JSON file saved as ""{0}"" file.", DestinationFile) Exit Do ElseIf status = "working" Then ' Pause for a few seconds Thread.Sleep(3000) Else Console.WriteLine(status) Exit Do End If Loop 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 Function CheckJobStatus(jobId As String) As String Using webClient As WebClient = New WebClient() ' Set API Key webClient.Headers.Add("x-api-key", API_KEY) Dim url As String = "https://api.pdf.co/v1/job/check?jobid=" + jobId Dim response As String = webClient.DownloadString(url) Dim json As JObject = JObject.Parse(response) Return Convert.ToString(json("status")) End Using End Function End Module

MultiPageTable-template1.yml

      
--- # Template that demonstrates parsing of multi-page table using only # macro expressions for the table start, end, and rows. # If macro expression cannot be written for every table row (for example, # if the table contains empty cells), try the second method demonstrated # in `MultiPageTable-template2.yml` template. templateVersion: 3 templatePriority: 0 sourceId: Multipage Table Test detectionRules: keywords: - Sample document with multi-page table fields: total: expression: 'TOTAL{{Spaces}}({{Number}})' dataType: decimal tables: - name: table1 start: # macro expression to find the table start in document expression: 'Item{{Spaces}}Description{{Spaces}}Price' end: # macro expression to find the table end in document expression: 'TOTAL{{Spaces}}{{Number}}' row: # macro expression to find table rows expression: '{{LineStart}}{{Spaces}}(?<itemNo>{{Digits}}){{Spaces}}(?<description>{{SentenceWithSingleSpaces}}){{Spaces}}(?<price>{{Number}}){{Spaces}}(?<qty>{{Digits}}){{Spaces}}(?<extPrice>{{Number}})' # output data types for columns columns: - name: itemNo type: integer - name: description type: string - name: price type: decimal - name: qty type: integer - name: extPrice type: decimal multipage: true

MultiPageTable-template2.yml

      
--- # Template that demonstrates parsing of multi-page table without using # macro expression for table rows. Rows and cells are extracted automatically # by specified column coordinates. Use `Template Editor` app to find the coordinates # (coordinates of the mouse cursor are displayed in the toolbar). templateVersion: 3 templatePriority: 0 sourceId: Multipage Table Test detectionRules: keywords: - Sample document with multi-page table fields: total: type: regex expression: 'TOTAL{{Spaces}}({{Number}})' dataType: decimal tables: - name: table1 # coordinate OR macro expression to find the table start on each document page start: #y: 136 expression: 'Item{{Spaces}}Description{{Spaces}}Price' # coordinate OR macro expression to find the table end on each document page end: #y: 787 expression: (Page {{Digits}} of {{Digits}})|(TOTAL{{Spaces}}{{Number}}) # left coordinate of the table (optional) left: 51 # right coordinate of the table (optional) right: 528 # column names, output data types and coordinates (left column edge) columns: - name: itemNo x: 51 type: integer - name: description x: 102 type: string - name: price x: 324 type: decimal - name: qty x: 396 type: integer - name: extPrice x: 441 type: decimal multipage: true

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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