Threading

Public Class Form1

    Dim amount As Integer = 30
    Dim pics(amount) As Bitmap
    Dim sw As Stopwatch = New Stopwatch()

    Dim t As Threading.Thread

    'For
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        sw.Restart()
        sw.Start()

        For i = 0 To amount - 1
            picset(i)
        Next

        Label1.Text = sw.ElapsedMilliseconds

    End Sub

    'Parallel.For
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click

        sw.Restart()
        sw.Start()

        Threading.Tasks.Parallel.For(0, amount - 1, AddressOf picset)

        Label2.Text = sw.ElapsedMilliseconds

    End Sub

    'Time waster
    Private Sub picset(ByVal i As Integer)

        pics(i) = New Bitmap(640, 480)

        For i2 = 0 To pics(i).Width - 1
            For i3 = 0 To pics(i).Height - 1
                pics(i).SetPixel(i2, i3, Color.Blue)
            Next
        Next

    End Sub

    'Background worker
    Private Sub Button3_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button3.Click

        sw.Restart()
        sw.Start()

        BackgroundWorker1.RunWorkerAsync()

    End Sub
    Private Sub BackgroundWorker1_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorker1.DoWork

        For i = 0 To amount - 1
            picset(i)
        Next

    End Sub
    Private Sub BackgroundWorker1_RunWorkerCompleted(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs) Handles BackgroundWorker1.RunWorkerCompleted
        Label3.Text = sw.ElapsedMilliseconds
    End Sub

    'Threadpool
    Private Sub Button4_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button4.Click

        Threading.ThreadPool.QueueUserWorkItem(AddressOf callthread1)

    End Sub
    Private Sub callthread1(ByVal stateInfo As Object)

        sw.Restart()
        sw.Start()

        For i = 0 To amount - 1
            picset(i)
        Next

        MsgBox(sw.ElapsedMilliseconds)

    End Sub

    'Thread
    Private Sub Button5_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button5.Click

        sw.Restart()
        sw.Start()

        t = New Threading.Thread(AddressOf callthread2)
        t.IsBackground = False
        t.SetApartmentState(Threading.ApartmentState.MTA)
        t.Start()

    End Sub
    Private Sub callthread2()

        For i = 0 To amount - 1
            picset(i)
        Next

        MsgBox(sw.ElapsedMilliseconds)

    End Sub

End Class