Visual Basic

Imports System.IO
Imports System.ComponentModel

Public Class Form1

    Private worker As System.ComponentModel.BackgroundWorker
    Private progress As Double


    Public Sub drawlazor(ByVal progress As Double)
        lazorbar.Size = New Size(lazorbar.Size.Width, 330 * progress)
        Refresh()

    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Me.Show()

        progress = 0

        worker = New System.ComponentModel.BackgroundWorker
        worker.WorkerReportsProgress = True
        worker.WorkerSupportsCancellation = True

        AddHandler worker.DoWork, New _
           DoWorkEventHandler(AddressOf OnWork)

        worker.RunWorkerAsync()
        While progress < 1
            System.Threading.Thread.Sleep(20)
            drawlazor(progress)
        End While
        worker.CancelAsync()


    End Sub

    Private Sub OnWork(ByVal sender As Object, _
                   ByVal e As DoWorkEventArgs)
        Dim oRead As New FileStream("file.bin", FileMode.Open)

        Dim index As Int64 = 0
        Dim filesize As Int64 = New FileInfo("file.bin").Length
        Dim count As Int32 = 1024 * 1024
        Dim oBuf(count) As Byte
        dostuff(oBuf)

        While index < filesize

            If (count > filesize - index) Then
                count = filesize - index
                Array.Resize(oBuf, count)
            End If

            oRead.Read(oBuf, 0, count)
            index += count

            progress = index / filesize

        End While

    End Sub

    Private Sub dostuff(ByVal oBuf() As Byte)
        ' pretend this is a parsing function that takes exactly 20ms to parse 1MB
        Threading.Thread.Sleep(20)
    End Sub
End Class

ikantspelwurdz wrote:

While progress < 1
System.Threading.Thread.Sleep(20)
drawlazor(progress)
End While

Range("B2").Cells(1).Value = something