Imports System.IO
Imports System.Windows.Forms
Imports Bytescout.BarCode

Public Partial Class Form1
    Inherits Form
    Public Sub New()
        InitializeComponent()

        For Each st As SymbologyType In [Enum].GetValues(GetType(SymbologyType))
            cmbBarcodeType.Items.Add(st)
        Next

        cmbBarcodeType.SelectedIndex = 0
        cmbImageFormat.SelectedIndex = 0
    End Sub

    Private Sub btnGenerate_Click(ByVal sender As Object, ByVal e As EventArgs) Handles btnGenerate.Click
        Dim folderBrowserDialog As New FolderBrowserDialog()
        folderBrowserDialog.Description = "Select output folder"

        If folderBrowserDialog.ShowDialog() <> DialogResult.OK Then
            Return
        End If

        Dim fileNameTemplate As String = tbFileNameTemplate.Text & "." & Convert.ToString(cmbImageFormat.SelectedItem).ToLower()
        Dim counterStartAt As UInteger = CUInt(Math.Truncate(nudCounterStartAt.Value))
        Dim counterStepBy As UInteger = CUInt(Math.Truncate(nudCounterStepBy.Value))
        Dim counterDigits As UInteger = Convert.ToUInt32(cmbCounterDigits.Text)

        If Not fileNameTemplate.Contains("[N]") Then
            MessageBox.Show("File name template does not contain the counter placeholder [N]")
            Return
        End If

        Dim valueTemplate As String = tbValueTemplate.Text
        Dim valueStartAt As UInteger = CUInt(Math.Truncate(nudValueStartAt.Value))
        Dim valueStepBy As UInteger = CUInt(Math.Truncate(nudValueStepBy.Value))
        Dim valueEndAt As UInteger = CUInt(Math.Truncate(nudValueEndAt.Value))
        Dim valueDigits As UInteger = Convert.ToUInt32(cmbValueDigits.Text)

        If Not valueTemplate.Contains("[N]") Then
            MessageBox.Show("Barcode value template does not contain the counter placeholder [N]")
            Return
        End If

        Cursor = Cursors.WaitCursor
        progressBar.Visible = True
        btnGenerate.Text = "Stop"

        Try
            progressBar.Value = CInt(valueStartAt)
            progressBar.Minimum = CInt(valueStartAt)
            progressBar.Maximum = CInt(valueEndAt)
            progressBar.Step = CInt(valueStepBy)

            GenerateBarcodes(valueTemplate, valueStartAt, valueEndAt, valueStepBy, valueDigits, fileNameTemplate, _
             counterStartAt, counterStepBy, counterDigits, folderBrowserDialog.SelectedPath)
        Catch exception As Exception
            MessageBox.Show(exception.Message)
        Finally
            Cursor = Cursors.Default
            progressBar.Visible = False
            btnGenerate.Text = "Generate multiple barcodes"
        End Try
    End Sub

    Private Sub GenerateBarcodes(valueTemplate As String, valueStartAt As UInteger, valueEndAt As UInteger, valueStepBy As UInteger, valueDigits As UInteger, fileNameTemplate As String, _
        counterStartAt As UInteger, counterStepBy As UInteger, counterDigits As UInteger, outputFolder As String)
        Dim barcode As New Barcode()
        barcode.RegistrationKey = "demo"
        barcode.RegistrationName = "demo"

        barcode.Symbology = CType(cmbBarcodeType.SelectedItem, SymbologyType)
        ' Set up additional barcode properties here.
        'barcode.AdditionalCaption = "...";

        Dim c As UInteger = counterStartAt

        Dim i As UInteger = valueStartAt
        While i <= valueEndAt
            Dim value As String = String.Format("{0:D" & valueDigits & "}", i)
            Dim counter As String = String.Format("{0:D" & counterDigits & "}", c)
            Dim fileName As String = fileNameTemplate.Replace("[N]", counter)

            progressBar.PerformStep()

            barcode.Value = valueTemplate.Replace("[N]", value)

            barcode.SaveImage(Path.Combine(outputFolder, fileName))

            c += counterStepBy

            Application.DoEvents()
            i += valueStepBy
        End While
    End Sub
End Class

Imports System.Collections.Generic
Imports System.Windows.Forms

NotInheritable Class Program
    Private Sub New()
    End Sub
    ''' <summary>
    ''' The main entry point for the application.
    ''' </summary>
    <STAThread> _
    Friend Shared Sub Main()
        Application.EnableVisualStyles()
        Application.SetCompatibleTextRenderingDefault(False)
        Application.Run(New Form1())
    End Sub
End Class