Understanding loop

Start learning VB 2005 EE and made a kind of Timing program.

Tried to show a text during time-call but it comes up only after the loop is
finished.
(TextBox2 in Sub Button1_Click)
I do not understand why.
Cannot find it either on internet.
Please can anyone explain to me the reason.
Here the code so far:



Public Class Form1

Dim Uitlezing As Single = 0
Dim Inlezing As Single = 0
Dim BeginTime As Double = 0
Dim FinishTime As Double = 0
Dim ElapsedTime As Single = 0
Dim Wachttijd As Single = 5
Dim Wachttext As String = ""
Dim TotalTime As Single = 0

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

TextBox2.Text = "Program Runs"

Call InitializeTimer(Uitlezing, Wachttijd)

Inlezing = Uitlezing
Uitlezing = 0

TextBox1.Text = "Waiting Time was" & " " & Str(Inlezing) & " Seconds."

End Sub


Private Sub InitializeTimer(ByRef Uitlezing As Single, ByRef Wachttijd As
Single)

ElapsedTime = 0

BeginTime = Microsoft.VisualBasic.DateAndTime.Timer

Do While ElapsedTime < Wachttijd

FinishTime = Microsoft.VisualBasic.DateAndTime.Timer
ElapsedTime = (FinishTime - BeginTime)

Loop

Uitlezing = ElapsedTime

End Sub


Private Sub Wait_Click(ByVal sender As System.Object, ByVal e As
System.EventArgs) Handles Wait.Click

Wachttext = MaskedTextBox1.Text
Wachttijd = Single.Parse(Wachttext)

Call InitializeTimer(Uitlezing, Wachttijd)

TotalTime = Inlezing + Uitlezing
TextBox2.Text = "Total Time is" & " " & Str(TotalTime) & " " & "Seconds"

End Sub

End Class




Many thanks,
Arie

A.G.van Staveren