return to previous page explore PDF To TEXT endpoint

Async file upload and async PDF to Text - VB.NET

PDF To TEXT sample in VB.NET demonstrating ‘Async file upload and async PDF to Text’

View on GitHub Download Source Code (.zip)

Module1.vb

﻿Imports System.IO
Imports System.Net
Imports System.Threading
Imports Newtonsoft.Json
Imports Newtonsoft.Json.Linq

Module Module1

    ' The authentication key (API Key).
    ' Get your own by registering at https://app.pdf.co
    Const API_KEY As String = "***********************************"

    ' Source PDF file
    Const SourceFile As String = ".\sample.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"
    ' (!) Make asynchronous job
    Const Async As Boolean = True


    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("async", Async)

                ' Convert dictionary of params to JSON
                Dim jsonPayload As String = JsonConvert.SerializeObject(parameters)

                Try
                    ' 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

                        ' Asynchronous job ID
                        Dim jobId As String = json("jobId").ToString()
                        ' URL of generated TXT 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 TXT file
                                webClient.DownloadFile(resultFileUrl, DestinationFile)

                                Console.WriteLine("Generated TXT 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

                Catch ex As WebException
                    Console.WriteLine(ex.ToString())
                End Try

            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

    ''' <summary>
    ''' Check Job Status
    ''' </summary>
    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

Resources.Designer.vb

﻿'------------------------------------------------------------------------------
' <auto-generated>
'     This code was generated by a tool.
'     Runtime Version:4.0.30319.42000
'
'     Changes to this file may cause incorrect behavior and will be lost if
'     the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------

Option Strict On
Option Explicit On


Namespace My.Resources

	'This class was auto-generated by the StronglyTypedResourceBuilder
	'class via a tool like ResGen or Visual Studio.
	'To add or remove a member, edit your .ResX file then rerun ResGen
	'with the /str option, or rebuild your VS project.
	'''<summary>
	'''  A strongly-typed resource class, for looking up localized strings, etc.
	'''</summary>
	<Global.System.CodeDom.Compiler.GeneratedCodeAttribute("System.Resources.Tools.StronglyTypedResourceBuilder", "4.0.0.0"), _
	 Global.System.Diagnostics.DebuggerNonUserCodeAttribute(), _
	 Global.System.Runtime.CompilerServices.CompilerGeneratedAttribute(), _
	 Global.Microsoft.VisualBasic.HideModuleNameAttribute()> _
	Friend Module Resources

		Private resourceMan As Global.System.Resources.ResourceManager

		Private resourceCulture As Global.System.Globalization.CultureInfo

		'''<summary>
		'''  Returns the cached ResourceManager instance used by this class.
		'''</summary>
		<Global.System.ComponentModel.EditorBrowsableAttribute(Global.System.ComponentModel.EditorBrowsableState.Advanced)> _
		Friend ReadOnly Property ResourceManager() As Global.System.Resources.ResourceManager
			Get
				If Object.ReferenceEquals(resourceMan, Nothing) Then
					Dim temp As Global.System.Resources.ResourceManager = New Global.System.Resources.ResourceManager("ByteScoutWebApiExample.Resources", GetType(Resources).Assembly)
					resourceMan = temp
				End If
				Return resourceMan
			End Get
		End Property

		'''<summary>
		'''  Overrides the current thread's CurrentUICulture property for all
		'''  resource lookups using this strongly typed resource class.
		'''</summary>
		<Global.System.ComponentModel.EditorBrowsableAttribute(Global.System.ComponentModel.EditorBrowsableState.Advanced)> _
		Friend Property Culture() As Global.System.Globalization.CultureInfo
			Get
				Return resourceCulture
			End Get
			Set(ByVal value As Global.System.Globalization.CultureInfo)
				resourceCulture = value
			End Set
		End Property
	End Module
End Namespace

Settings.Designer.vb

﻿'------------------------------------------------------------------------------
' <auto-generated>
'     This code was generated by a tool.
'     Runtime Version:4.0.30319.42000
'
'     Changes to this file may cause incorrect behavior and will be lost if
'     the code is regenerated.
' </auto-generated>
'------------------------------------------------------------------------------

Option Strict On
Option Explicit On


Namespace My

	<Global.System.Runtime.CompilerServices.CompilerGeneratedAttribute(), _
	 Global.System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "11.0.0.0"), _
	 Global.System.ComponentModel.EditorBrowsableAttribute(Global.System.ComponentModel.EditorBrowsableState.Advanced)> _
	Partial Friend NotInheritable Class MySettings
		Inherits Global.System.Configuration.ApplicationSettingsBase

		Private Shared defaultInstance As MySettings = CType(Global.System.Configuration.ApplicationSettingsBase.Synchronized(New MySettings), MySettings)

#Region "My.Settings Auto-Save Functionality"
#If _MyType = "WindowsForms" Then
        Private Shared addedHandler As Boolean

        Private Shared addedHandlerLockObject As New Object

        <Global.System.Diagnostics.DebuggerNonUserCodeAttribute(), Global.System.ComponentModel.EditorBrowsableAttribute(Global.System.ComponentModel.EditorBrowsableState.Advanced)> _
        Private Shared Sub AutoSaveSettings(ByVal sender As Global.System.Object, ByVal e As Global.System.EventArgs)
            If My.Application.SaveMySettingsOnExit Then
                My.Settings.Save()
            End If
        End Sub
#End If
#End Region

		Public Shared ReadOnly Property [Default]() As MySettings
			Get

#If _MyType = "WindowsForms" Then
                   If Not addedHandler Then
                        SyncLock addedHandlerLockObject
                            If Not addedHandler Then
                                AddHandler My.Application.Shutdown, AddressOf AutoSaveSettings
                                addedHandler = True
                            End If
                        End SyncLock
                    End If
#End If
				Return defaultInstance
			End Get
		End Property
	End Class
End Namespace

Namespace My

	<Global.Microsoft.VisualBasic.HideModuleNameAttribute(), _
	 Global.System.Diagnostics.DebuggerNonUserCodeAttribute(), _
	 Global.System.Runtime.CompilerServices.CompilerGeneratedAttribute()> _
	Friend Module MySettingsProperty

		<Global.System.ComponentModel.Design.HelpKeywordAttribute("My.Settings")> _
		Friend ReadOnly Property Settings() As Global.ByteScoutWebApiExample.My.MySettings
			Get
				Return Global.ByteScoutWebApiExample.My.MySettings.Default
			End Get
		End Property
	End Module
End Namespace

PDF.co Web API: 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.

Get your PDF.co API key here!

Async file upload and async PDF to Text - VB.NET

Module1.vb

Resources.Designer.vb

Settings.Designer.vb

Download Source Code (.zip)

return to the previous page explore PDF To TEXT endpoint