timer event overflows

Question

User297437924 posted

I have a website that lets the user save an object.   This 'save' takes a long time to execute.   I put a save icon on the menu.   The icon goes to a web form.   The page displays an animated hourglass to show time passing.    In the Form_Load command, I put a timer that I want to execute only once.   In the timer event, I put 'timer1.enabled = false'.   Then I call the lengthy save routine (in that event).   I have the timer interval set for 100.  (I don't call the 'save' event in the form-load event because the form would not appear until the lengthy operation is over.)

But I get an overflow.   I think what is happening is that the timer1 event takes so long that it fires more events, even though 'timer1.enabled' was set to false.   

Is there a way around this?

Answer 1

User475983607 posted

Is there a way around this?

The design does not sound correct for a web application but then again I cannot see the code.  Share code that reproduces this issue and the actual exception if you want or need a community code review.

Answer 2

User297437924 posted

I replaced the form with the timer by a form with a button, and now I require the user to click the button.   The OnClientClick event displays a GIF animation of an hourglass, and the lengthy operation is started.   

My original goal had been that the icon on the menu would take the user to a form, and the form would automatically start saving the object, as well as display the hourglass.   This ended with an overflow message.

As I recall the page load event had something like

if not page.ispostback then
timer1.interval = 100
end if

And then the timer1_tick event had this:

timer1.enabled  false
'call lengthy operation

I think what's going is that the 'timer1.enabled=false' statement never gets a chance to stop the timer, because the lengthy operation prevents the next timer ticks from learning that they should stop.

Answer 3

User475983607 posted

The timer fires every 100 ms on the server.  Why?  What are you timing?   How long a process runs?   Is there anyway you can provide enough sample code the community can run to reproduce the same issue?

Answer 4

User288213138 posted

Hi RateFor,

I think what's going is that the 'timer1.enabled=false' statement never gets a chance to stop the timer, because the lengthy operation prevents the next timer ticks from learning that they should stop.

According to your description, I cannot reproduce your problem.

But here a demo for you as a reference about how to use the timer control.

<asp:ScriptManager ID="ScriptManager1" runat="server">
            </asp:ScriptManager>
            <asp:UpdatePanel ID="UpdatePanel1" runat="server">
                <ContentTemplate>
                    <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>         
                     <asp:Timer ID="Timer1" runat="server" OnTick="GetTime" Interval="100" />                              
                </ContentTemplate>
            </asp:UpdatePanel>

Protected Sub GetTime(ByVal sender As Object, ByVal e As EventArgs)
    Label1.Text = DateTime.Now.ToString("hh:mm:ss tt")
End Sub

If you can't solve the problem, please share your code with us.

Best regards,

Sam

Answer 5

User297437924 posted

I'm not timing anything.   I'm just want the timer to fire once and only once.   '100ms' is just an arbitrary number.   The page will not display if I do the lengthy operation in the page load event, - it will be invisible until that event is over.   Thats why I have the timer - so that the page-load event will be completed, the page will display (with an animated hourglass) and then the lengthy operation will commence.   When the lengthy operation is over, it redirects to a 'finished' page.

Answer 6

User297437924 posted

I probably should forget about a timer, and start a thread.