Timer.Elapsed event doesn't want to fire

[Nathan Sokalski]

I am trying to learn how to use the System.Timers.T imer control to perform
an action every certain amount of time. However, the Elapsed event doesn't
want to fire, but I can't figure out why. I looked at several code examples
online, but I think I was doing everything the same way they were. Does
anybody have a complete example in VB.NET (the whole aspx and aspx.vb file
so I know I am including everything) that I can look at? Any help would be
appreciated. Thanks.
--
Nathan Sokalski
njsokalski@hotm ail.com

http://www.nathansokalski.com/

[Anand[MVP]]

RE: Timer.Elapsed event doesn't want to fire

Are you trying to use this in a ASP.NET Page? Pages live only for the time of
the request. Once a request is served, the Page class is destroyed.

--
Rgds,
Anand
VB.NET MVP

http://www.dotnetindia.com

"Nathan Sokalski" wrote:
[color=blue]
> I am trying to learn how to use the System.Timers.T imer control to perform
> an action every certain amount of time. However, the Elapsed event doesn't
> want to fire, but I can't figure out why. I looked at several code examples
> online, but I think I was doing everything the same way they were. Does
> anybody have a complete example in VB.NET (the whole aspx and aspx.vb file
> so I know I am including everything) that I can look at? Any help would be
> appreciated. Thanks.
> --
> Nathan Sokalski
> njsokalski@hotm ail.com
> http://www.nathansokalski.com/
>
>
>[/color]

[stand__sure]

Re: Timer.Elapsed event doesn't want to fire

for asp.net, anand is correct.

for all languages in general, timers are not guaranteed to fire on
time. this happens for two reason: 1) task switching at the CPU; and
2) WM_TIMER messages have a lower priority than other messages (like
device input)

[Rothariger]

RE: Timer.Elapsed event doesn't want to fire

hi, there are two types of timers, one is at windows forms, and the other is
at components, one works just fine, and the other its just crap... i didnt
know the difference, but so is it...


salute!

"Nathan Sokalski" wrote:
[color=blue]
> I am trying to learn how to use the System.Timers.T imer control to perform
> an action every certain amount of time. However, the Elapsed event doesn't
> want to fire, but I can't figure out why. I looked at several code examples
> online, but I think I was doing everything the same way they were. Does
> anybody have a complete example in VB.NET (the whole aspx and aspx.vb file
> so I know I am including everything) that I can look at? Any help would be
> appreciated. Thanks.
> --
> Nathan Sokalski
> njsokalski@hotm ail.com
> http://www.nathansokalski.com/
>
>
>[/color]

[Nathan Sokalski]

Re: Timer.Elapsed event doesn't want to fire

I understand that that is true for the actual pages, but is there a way to
use a timer in the Global.asax.vb file? Doesn't that live the entire life of
the application? My basic goal is to find a way to periodically send myself
stats about what people do at my site, and send email newsletters. And there
is obviously some purpose for the System.Timers.T imer in ASP.NET since
Visual Studio lets you add it to an ASP.NET webform.
--
Nathan Sokalski
njsokalski@hotm ail.com

http://www.nathansokalski.com/

"Anand[MVP]" <AnandMVP@discu ssions.microsof t.com> wrote in message
news:EDD9C189-3F89-4A4D-8476-7373EC3A02B1@mi crosoft.com...[color=blue]
> Are you trying to use this in a ASP.NET Page? Pages live only for the time
> of
> the request. Once a request is served, the Page class is destroyed.
>
> --
> Rgds,
> Anand
> VB.NET MVP
> http://www.dotnetindia.com
>
>
> "Nathan Sokalski" wrote:
>[color=green]
>> I am trying to learn how to use the System.Timers.T imer control to
>> perform
>> an action every certain amount of time. However, the Elapsed event
>> doesn't
>> want to fire, but I can't figure out why. I looked at several code
>> examples
>> online, but I think I was doing everything the same way they were. Does
>> anybody have a complete example in VB.NET (the whole aspx and aspx.vb
>> file
>> so I know I am including everything) that I can look at? Any help would
>> be
>> appreciated. Thanks.
>> --
>> Nathan Sokalski
>> njsokalski@hotm ail.com
>> http://www.nathansokalski.com/
>>
>>
>>[/color][/color]

[Peter Bromberg [C# MVP]]

Re: Timer.Elapsed event doesn't want to fire

Here is an example. for the full context, see:

http://www.eggheadcafe.com/articles/20040607.asp

Hope this helps.
--Peter

using System;
using System.Web;
using System.Threadin g;
using System.Data;
using System.Data.Sql Client;
using System.Configur ation;

namespace BlackbeltBLL {
public class BackgroundServi ce : IHttpModule {
static Timer timer;
int interval = 5000;
public String ModuleName {
get { return "BackgroundServ ice"; }
}

public void Init(HttpApplic ation application) {
// Wire-up application events
if (timer == null)
timer = new Timer(new
TimerCallback(S cheduledWorkCal lback),
application.Con text, interval, interval);
}

public void Dispose() {
timer = null;
}

private void ScheduledWorkCa llback (object sender) {
HttpContext context = (HttpContext) sender;
Poll(context);
}

void DoSomething (HttpContext context) {
}

#region DB Poll
void Poll (HttpContext context) {
SqlConnection connection = new
SqlConnection(C onfigurationSet tings.AppSettin gs["Northwind"]);
SqlCommand command = new
SqlCommand("SEL ECT * FROM changenotificat ion", connection);
SqlDataReader reader;
string key =
ConfigurationSe ttings.AppSetti ngs["SqlDepende ncy"];
connection.Open ();
reader = command.Execute Reader();
while (reader.Read()) {
string tableKey = String.Format(k ey, reader["Table"]);
if (context.Cache[tableKey] != null) {
int changeKey =
int.Parse( context.Cache[ String.Format(k ey,
reader["Table"])].ToString() );
if (changeKey != int.Parse(
reader["ChangeID"].ToString() ))
context.Cache.R emove(tableKey) ;
}
}
connection.Clos e();
}
#endregion
}
}


Nathan Sokalski wrote:[color=blue]
> I understand that that is true for the actual pages, but is there a way to
> use a timer in the Global.asax.vb file? Doesn't that live the entire life of
> the application? My basic goal is to find a way to periodically send myself
> stats about what people do at my site, and send email newsletters. And there
> is obviously some purpose for the System.Timers.T imer in ASP.NET since
> Visual Studio lets you add it to an ASP.NET webform.
> --
> Nathan Sokalski
> njsokalski@hotm ail.com
> http://www.nathansokalski.com/
> "Anand[MVP]" <AnandMVP@discu ssions.microsof t.com> wrote in message
> news:EDD9C189-3F89-4A4D-8476-7373EC3A02B1@mi crosoft.com...[color=green]
> > Are you trying to use this in a ASP.NET Page? Pages live only for the time
> > of
> > the request. Once a request is served, the Page class is destroyed.
> >
> > --
> > Rgds,
> > Anand
> > VB.NET MVP
> > http://www.dotnetindia.com
> >
> >
> > "Nathan Sokalski" wrote:
> >[color=darkred]
> >> I am trying to learn how to use the System.Timers.T imer control to
> >> perform
> >> an action every certain amount of time. However, the Elapsed event
> >> doesn't
> >> want to fire, but I can't figure out why. I looked at several code
> >> examples
> >> online, but I think I was doing everything the same way they were. Does
> >> anybody have a complete example in VB.NET (the whole aspx and aspx.vb
> >> file
> >> so I know I am including everything) that I can look at? Any help would
> >> be
> >> appreciated. Thanks.
> >> --
> >> Nathan Sokalski
> >> njsokalski@hotm ail.com
> >> http://www.nathansokalski.com/
> >>
> >>
> >>[/color][/color][/color]