Imports System.Threading

Public Class frmOpdrachtLes5
    Private Sub BtnTeken_Click(sender As Object, e As EventArgs) Handles btnTeken.Click
        Dim stringResultaat As String
        Dim resultaat As Integer
        Dim prompt As String
        Dim titel As String
        prompt = "Geef max. aantal"
        titel = "Opdracht Les 5"
        stringResultaat = InputBox(prompt, titel)
        If IsNumeric(stringResultaat) Then
            resultaat = CInt(stringResultaat)
            'de gegevens van het tekstvak wordt in een variabele gestoken
            txtTekening.Text = ""
            If Not (resultaat >= "5") Or Not (resultaat <= "20") Then
                MessageBox.Show("Tussen 5 en 20 aub", "", MessageBoxButtons.OK)
                Exit Sub
            End If

			' Loop over alle rijen
			For sterRij As Integer = 0 To resultaat
				If sterRij % 2 = 0 Then
					' Loop over alle kolommen van links naar rechts
					For sterKolom As Integer = 0 To resultaat
						txtTekening.Text = ""
						For rij As Integer = 0 To resultaat
							For kolom As Integer = 0 To resultaat
								If rij = sterRij and kolom = sterKolom Then
									txtTekening.Text += '*'
								Else
									txtTekening.Text += '-'
								End If
							Next
							txtResultaat.Text += Environment.NewLine
						Next
						Thread.Sleep(200)
					Next
				Else
					' Loop over alle kolommen van rechts naar links
					For sterKolom As Integer = resultaat To 0 Step -1
						txtTekening.Text = ""
						For rij As Integer = 0 To resultaat
							For kolom As Integer = 0 To resultaat
								If rij = sterRij and kolom = sterKolom Then
									txtTekening.Text += '*'
								Else
									txtTekening.Text += '-'
								End If
							Next
							txtResultaat.Text += Environment.NewLine
						Next
						Thread.Sleep(200)
					Next
				End If
			Next


        End If
    End Sub
End Class