Convert PDF to Text in Multi-thread mode using C# and .NET

Complete code

using System;
using System.IO;
using System.Collections.Generic;
using System.Threading;
using SautinSoft;

namespace Sample
    class Sample
        static void Main(string[] args)
        public class TArgument
            public string PdfFile { get; set; }
            public int PageNumber { get; set; }
        public static void ConvertPdfToTextInThread()
            string pdfs = Path.GetFullPath(@"..\..\..\");
            string[] files = Directory.GetFiles(pdfs, "*.pdf");

            List<Thread> threads = new List<Thread>();
            for (int i = 0; i < files.Length; i++)
                TArgument targ = new TArgument()
                    PdfFile = files[i],
                    PageNumber = 1

                var t = new Thread((a) => ConvertToText(a));

            foreach (var thread in threads)

        public static void ConvertToText(object targ)
            TArgument targum = (TArgument)targ;
            string pdfFile = targum.PdfFile;
            int page = targum.PageNumber;

            string textFile = Path.GetFileNameWithoutExtension(pdfFile) + ".txt";
                                  // Get your free 30-day key here:   
            SautinSoft.PdfFocus f = new SautinSoft.PdfFocus();

            f.WordOptions.ShowInvisibleText = true;

            bool done = false;

            if (f.PageCount > 0)
                if (page >= f.PageCount)
                    page = 1;

                if (f.ToText(textFile, page, page) == 0)
                    done = true;

            if (done)
                Console.WriteLine("{0}\t - Done!", Path.GetFileName(pdfFile));
                System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(textFile) { UseShellExecute = true });
                Console.WriteLine("{0}\t - Error!", Path.GetFileName(pdfFile));


Imports System.IO
Imports System.Drawing.Imaging
Imports System.Collections.Generic
Imports System.Threading
Imports SautinSoft

Module Sample

    Sub Main()
    End Sub
    Public Class TArgument
        Public Property PdfFile() As String
        Public Property PageNumber() As Integer
    End Class
    Public Sub ConvertPdfToTextInThread()
        Dim pdfs As String = Path.GetFullPath("..\..\..\")
        Dim files() As String = Directory.GetFiles(pdfs, "*.pdf")

        Dim threads As New List(Of Thread)()
        For i As Integer = 0 To files.Length - 1
            Dim targ As New TArgument() With {
                .PdfFile = files(i),
                .PageNumber = 1

            Dim t = New Thread(Sub(a) ConvertToText(a))
        Next i

        For Each t As Thread In threads
        Next t
    End Sub

    Public Sub ConvertToText(ByVal targ As Object)
        Dim targum As TArgument = DirectCast(targ, TArgument)
        Dim pdfFile As String = targum.PdfFile
        Dim page As Integer = targum.PageNumber

        Dim textFile As String = Path.GetFileNameWithoutExtension(pdfFile) + ".txt"
                                ' Get your free 30-day key here: 
        Dim f As New SautinSoft.PdfFocus()

        f.WordOptions.ShowInvisibleText = True


        Dim done As Boolean = False

        If f.PageCount > 0 Then
            If page >= f.PageCount Then
                page = 1
            End If

            If f.ToText(textFile, page, page) = 0 Then
                done = True
            End If
        End If

        If done Then
            Console.WriteLine("{0}" & ControlChars.Tab & " - Done!", Path.GetFileName(pdfFile))
            System.Diagnostics.Process.Start(New System.Diagnostics.ProcessStartInfo(textFile) With {.UseShellExecute = True})
            Console.WriteLine("{0}" & ControlChars.Tab & " - Error!", Path.GetFileName(pdfFile))
        End If
    End Sub
End Module


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