[RESOLVED] Execute While loop when button pressed

Dear all,

I am trying to code with visual basic 2010.

I have 2 button START and STOP . if start button pressed while loop should executed with printing "hello" first time and "welcome"in second time . This loop should executed evey 5s. If stop button pressed while loop should end print " stop button pressed on same rich textbox

Code:

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Public Class Form1

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button_click.Click
     
            Timer1.Interval = 1000 '3 seconds
            Timer1.Enabled = True
        RichTextBox1.Text = "hello"
        RichTextBox1.Text = "\n wait\n"


    End Sub


    Private Sub Button_stop_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button_stop.Click
        Timer1.Enabled = False
        RichTextBox1.Text = "Button stop pressed"
    End Sub
End Class

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Code:

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Option Explicit On



Public Class Form1
    Declare Sub Sleep Lib "kernel32" (ByVal milliseconds As Long)
    Dim stopclick As Boolean = False
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button_click.Click


        While True
            Application.DoEvents()
            sleep_program()
            RichTextBox1.Text = "hello"
            sleep_program()
            RichTextBox1.AppendText(RichTextBox1.Text)
            ' Perform the while statements
            If stopclick Then
                stopclick = False
                Exit While
            End If
        End While

       


    End Sub


    Private Sub Button_stop_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button_stop.Click
        stopclick = True
        RichTextBox1.Text = "Button stop pressed"
    End Sub

    Sub sleep_program()
        Threading.Thread.Sleep(3000)
    End Sub
End Class

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Modified code as below. But i could not able to acheieve below thing

I have two button start and stop.

start button to start while loop and stop button to stop the while loop

when button has pressed richtextbox has to print "hello" -> delay(1000)-> print "welcome" ->delay(1000)-> print "hello" ->delay(1000)-> print "welcome" -> and so on.If button stop pressed it should stop printing "welcome" and "hello"

Why not use a timer and just use the buttons to change the state of what the timer code is doing.

Code:

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Public Class Form1
    Private StepState As Boolean

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button_click.Click
     
            Timer1.Interval = 1000 '1 second
            Timer1.Enabled = True
            StepState = False  'always start with hello
            RichTextBox1.Text = "Hello"
    End Sub


    Private Sub Button_stop_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button_stop.Click
        Timer1.Enabled = False
        RichTextBox1.Text = "Button stop pressed"
    End Sub

    Private Sub Timer1_Tick(sender As System.Object, e As System.EventArgs) Handles Timer1.Tick
        If Timer1.Enabled = True    'Might get one tick event after timer disabled, so verify it is still enabled
            StepState = Not StepState
            If StepState Then
              RichTextBox1.Text = "Welcome"
            Else
              RichTextBox1.Text = "Hello"
            End If
        End If
    End Sub
End Class

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I almost totally agree with passel. The one situation where using a loop would make sense here is if this was for a class (where it might be a requirement) or if those sleep_program() calls didn't really sleep. For all other cases, a timer would be the way to go.