[RESOLVED] Perform action only when the time exactly match

[VB.NET Developer]

Stupid question, but...
I want to show my second form only when time will be exactly 08:00:00 and again at 15:00:00.
Kinda works - it shown msgbox when time does not match, but if it match, form2 constantly opens when I close it, althought it should open only once and immediately should open msgboxes every one seconds, because time does not match.
Second, I set the interval to 0.5 sec to check time (because there can be mismatch!), but the msgbox still opens every 1 second. Of course it´s also altered inside timer in properties.

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Timer1.Enabled = True
        Timer1.Interval = 500
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Label1.Text = Date.Now.ToString("HH")
        Label2.Text = Date.Now.ToString("mm")
        Label3.Text = Date.Now.ToString("ss")
        If Label1.Text = "08" And Label2.Text = "00" And Label3.Text = "00" Then
            Form2.Show()
            Timer1.Stop()
            Timer1.Start()
        Else
            MsgBox("Time does not match, sorry!")
        End If
        If Label1.Text = "15" And Label2.Text = "00" And Label3.Text = "00" Then
            Form2.Show()
        Else
        End If
    End Sub

[ChrisE]

hi

try this way
add a Label to Form1
and I just opened Form2 when the set Time was reached

Option Strict On

Public Class Form1

    Dim WithEvents timer1 As New Timer With {.Enabled = True, .Interval = 1000}
    ' alarmtime 
    Dim alarmTime As DateTime = DateTime.Parse("19:08:00")

   


    Private Sub timér1_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles timer1.Tick
        ' show time
        Label1.Text = DateTime.Now.ToString("HHH:mm:ss")
        ' compare the time
        If DateTime.Now > alarmTime Then
            ' time's up do somthing
            Form2.Show()
            timer1.Stop()
        End If
    End Sub
End Class

[VB.NET Developer]

Option Strict On
Public Class Form1
    Dim WithEvents timer2 As New Timer With {.Enabled = True, .Interval = 1000}
    ' alarmtime 
    Dim alarmTime As DateTime = DateTime.Parse("08:00:00")
    Private Sub timer2_Tick(ByVal sender As Object, ByVal e As System.EventArgs)
        ' show time
        Label1.Text = DateTime.Now.ToString("HHH:mm:ss")
        ' compare the time
        If DateTime.Now > alarmTime Then
            ' time's up do somthing
            Form2.Show()
            timer2.Stop()
        End If
    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        timer2.Start()
    End Sub
End Class

it does not work... Form2 isn´t displayed and Label1.Text is Label1.

[ChrisE]

you missed something

see Blue

 Private Sub timer2_Tick(ByVal sender As Object, ByVal e As System.EventArgs) Handles timer2.Tick

you also don't have to start the Timer in Form_Load

[VB.NET Developer]

this works for me:

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Timer1.Enabled = True
        Timer2.Enabled = True
    End Sub

    Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
        Label1.Text = Date.Now.ToString("HH:mm:ss")
    End Sub

    Private Sub Timer2_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer2.Tick
        If Label1.Text = "08:00:00" Or Label1.Text = "15:00:00" Then
            Form2.Show()
        Else
        End If
    End Sub

Solved!

[jmcilhinney]

Instead of having the Timer Tick every second and comparing the current time, why not just have the Timer Tick at the time you want? Just calculate the time between now and the next Tick and set that as the Interval. A Timer does drift a bit but not so much in that short period that it should matter. If you want it more accurate then set the Interval so that it Ticks a minute before and then set the Interval to whatever time remains. The drift over that last minute will be negligible.