Member Avatar for jamal87

hey working on a program. i have a timer and want it to countdown to zero when the button is clicked any ideas i'd appreciate.cheers.

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The suggestions from and illustrate the common Windows Forms pattern: start a timer on click, step a counter each tick, and update a label. That works for simple, short countdowns. Two extra points rarely mentioned here: a server-side timer does not update a browser (for ASP.NET use client-side JavaScript or a push mechanism), and repeated tick-based timers can drift over longer periods — computing remaining time from a fixed end time avoids that drift.

An alternative approach that avoids a Timer control is to compute an end time and update the label asynchronously. This keeps the UI responsive, makes the countdown accurate across small delays, and allows cancellation:

Private cancellation As System.Threading.CancellationTokenSource

Private Async Sub StartButton_Click(sender As Object, e As EventArgs) Handles StartButton.Click
    Dim seconds As Integer = 30
    StartButton.Enabled = False
    cancellation = New System.Threading.CancellationTokenSource()
    Dim endTime = DateTime.UtcNow.AddSeconds(seconds)
    Try
        While DateTime.UtcNow < endTime AndAlso Not cancellation.Token.IsCancellationRequested
            Dim remaining As TimeSpan = endTime - DateTime.UtcNow
            LabelTime.Text = remaining.ToString("mm\:ss")
            Await Task.Delay(250, cancellation.Token)
        End While
        LabelTime.Text = "00:00"
    Catch ex As OperationCanceledException
        ' cancelled
    Finally
        StartButton.Enabled = True
        cancellation = Nothing
    End Try
End Sub

Practical tips: marshal UI updates with Invoke when using background timers, prevent concurrent countdowns by disabling the start control or using a CancellationToken, clamp negatives so display never goes below zero, and prefer client-side JS for web pages if the countdown must be visible in a browser.

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Member Avatar for farooqaaa

Add this under "Public class Form1 ....":

Dim count As Integer = 100

Add a label to the form.

Add this to the Button_Click event code:

Timer1.Start()

Double-click the timer to add the Timer_Tick event and use this code:

count -= 1
Label1.Text = count

Thanks

Edited by farooqaaa because: n/a
Member Avatar for L0u3 
Public Class Form1

    Dim Count As Integer
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Count = 10 ' Edit this value
        With Timer1
            .Interval = 1000 ' 1 sec
            .Enabled = True ' Start Timer
        End With
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Count -= 1 ' Same as Count = Count - 1
        Console.Write(Count) ' Write Output
        If Count <= 0 Then
            Timer1.Enabled = False ' Stop Timer
            '''''''''''''''''''''''''''''''''''''''''
            ''  D O   S O M E T H I N G   H E R E  ''
            ''    C O U N T D O W N   D O N E      ''
            '''''''''''''''''''''''''''''''''''''''''
        End If
    End Sub

End Class
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