ByteScout PDF Extractor SDK – VB.NET – Parallel Processing of PDF files

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ByteScout PDF Extractor SDK – VB.NET – Parallel Processing of PDF files

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ByteScout-PDF-Extractor-SDK-VB-NET-Parallel-Processing-of-PDF-files.pdf

parallel processing of PDF files in VB.NET with ByteScout PDF Extractor SDK

parallel processing of PDF files in VB.NET

Every ByteScout tool contains example VB.NET source codes that you can find here or in the folder with installed ByteScout product. ByteScout PDF Extractor SDK was made to help with parallel processing of PDF files in VB.NET. ByteScout PDF Extractor SDK is the Software Development Kit (SDK) that is designed to help developers with data extraction from unstructured documents like pdf, tiff, scans, images, scanned and electronic forms. The library is powered by OCR, computer vision and AI to provide unique functionality like table detection, automatic table structure extraction, data restoration, data restructuring and reconstruction. Supports PDF, TIFF, PNG, JPG images as input and can output CSV, XML, JSON formatted data. Includes full set of utilities like pdf splitter, pdf merger, searchable pdf maker.

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. In order to implement this functionality, you should copy and paste code below into your app using code editor. Then compile and run your application. Use of ByteScout PDF Extractor SDK in VB.NET is also explained in the documentation included along with the product.

Visit our website provides for free trial version of ByteScout PDF Extractor SDK. Free trial includes lots of source code samples to help you with your VB.NET project.

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Module1.vb

      Imports System.IO
Imports System.Threading
Imports Bytescout.PDFExtractor

Module Module1

    ' Limit to 4 threads in queue.
    ' Set this value to number of your processor cores for max performance.
    ReadOnly ThreadLimiter As Semaphore = New Semaphore(4, 4)

    <MTAThread()>
    Sub Main()

        ' Get all PDF files in a folder
        Dim files = Directory.GetFiles("..\..\..\..\", "*.pdf")
        ' Array of events to wait
        Dim doneEvents(files.Length - 1) As ManualResetEvent

        For i As Integer = 0 To files.Length - 1

            ' Wait for the queue
            ThreadLimiter.WaitOne()

            ' Start thread with filename and event in params
            doneEvents(i) = New ManualResetEvent(False)
            Dim threadData As Object = New Object() {files(i), doneEvents(i)}
            ThreadPool.QueueUserWorkItem(AddressOf ConvertPdfToTxt, threadData)

        Next

        ' Wait until all threads finish
        WaitHandle.WaitAll(doneEvents)

        Console.WriteLine()
        Console.WriteLine("All is done.")
        Console.WriteLine()
        Console.WriteLine("Press any key to exit...")
        Console.ReadKey()

    End Sub

    Private Sub ConvertPdfToTxt(ByVal state As Object)

        ' Get filename and event from params
        Dim file As String = state(0)
        Dim doneEvent As ManualResetEvent = state(1)

        Dim resultFileName = Path.GetFileName(file) + ".txt"

        Try

            Console.WriteLine("Converting " + file)

            Using extractor As New TextExtractor("demo", "demo")

                extractor.LoadDocumentFromFile(file)
                extractor.SaveTextToFile(resultFileName)

            End Using

            Console.WriteLine("Finished " + resultFileName)

        Finally

            ' Signal the thread is finished
            doneEvent.Set()
            ' Release semaphore
            ThreadLimiter.Release()

        End Try

    End Sub

End Module