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It seems that the issue is that issuing SqlCommands on a SqlClient seems to
take over the current thread completely. I thought I could do this all on
the UI thread with a simple Timer control, but that ain't happenin'. Any
ideas on how I can get my Timer control to Tick during SqlCommand
executions? That would be a much simpler and preferable solution than a
separate thread. But I'm open to a separate worker thread if necessary.

Thanks in advance,
Michael C.

"Michael C" <mi*******@opto nline.net> wrote in message
news:y2******** **************@ news4.srv.hcvln y.cv.net...

Hi all,

I'm now trying to update a status indicator via a Timer control on a worker thread. The status indicator is just a label on the main form, but I'm
having trouble figuring out exactly how to implement a separate worker
thread or asynchronous delegate that changes the label contents based on the Timer control's ticks. Are there any good examples out there and can you
point me to one or two?

Thanks,
Michael C.

Hi Michael,

See this fine article (there are 3 parts)
Safe, Simple Multithreading in Windows Forms
http://msdn.microsoft.com/library/de...ms06112002.asp

--
Miha Markic [MVP C#] - RightHand .NET consulting & development
miha at rthand com
www.rthand.com

"Michael C" <mi*******@opto nline.net> wrote in message
news:y2******** **************@ news4.srv.hcvln y.cv.net...

Hi all,

I'm now trying to update a status indicator via a Timer control on a worker thread. The status indicator is just a label on the main form, but I'm
having trouble figuring out exactly how to implement a separate worker
thread or asynchronous delegate that changes the label contents based on the Timer control's ticks. Are there any good examples out there and can you
point me to one or two?

Thanks,
Michael C.

Thanks for the link. He has the same example code in his book (Windows
Forms Programming in C#). Problem is that it doesn't solve my real problem,
which is that the SQL Query I'm executing seems to block the Timer() control
Tick event from ever executing. Even when I run the status update code on a
separate thread like in his book... How can I make my Timer() Tick like
it's supposed to?

Thanks,
Michael C.

"Miha Markic [MVP C#]" <miha at rthand com> wrote in message
news:up******** ******@tk2msftn gp13.phx.gbl...

Hi Michael,

See this fine article (there are 3 parts)
Safe, Simple Multithreading in Windows Forms
http://msdn.microsoft.com/library/de...ms06112002.asp
--
Miha Markic [MVP C#] - RightHand .NET consulting & development
miha at rthand com
www.rthand.com

"Michael C" <mi*******@opto nline.net> wrote in message
news:y2******** **************@ news4.srv.hcvln y.cv.net...

Hi all,

I'm now trying to update a status indicator via a Timer control on a

worker

thread. The status indicator is just a label on the main form, but I'm
having trouble figuring out exactly how to implement a separate worker
thread or asynchronous delegate that changes the label contents based on

the

Timer control's ticks. Are there any good examples out there and can you point me to one or two?

Thanks,
Michael C.

....P.S. I've even tried running my SQL Queries using asynchronous delegates
and setting the status updates code on it's own thread... I'm pretty much
lost as to what else I can possibly do to make this work...

Thanks,
Michael C.
"Miha Markic [MVP C#]" <miha at rthand com> wrote in message
news:up******** ******@tk2msftn gp13.phx.gbl...

Hi Michael,

See this fine article (there are 3 parts)
Safe, Simple Multithreading in Windows Forms
http://msdn.microsoft.com/library/de...ms06112002.asp
--
Miha Markic [MVP C#] - RightHand .NET consulting & development
miha at rthand com
www.rthand.com

"Michael C" <mi*******@opto nline.net> wrote in message
news:y2******** **************@ news4.srv.hcvln y.cv.net...

Hi all,

I'm now trying to update a status indicator via a Timer control on a

worker

thread. The status indicator is just a label on the main form, but I'm
having trouble figuring out exactly how to implement a separate worker
thread or asynchronous delegate that changes the label contents based on

the

Timer control's ticks. Are there any good examples out there and can you point me to one or two?

Thanks,
Michael C.

Any timers added in the UI (through the Timer control) require that the
message queue is being pumped in the UI thread for the timer to execute. If
you have executed a synchronous procedure on the UI thread, then the UI
thread will be blocked until the function returns and the timer will not
execute.

You might find that it's better to execute the sqlcommand on a worker thread
(the easiest way is through the thread pool), leaving you free to update the
UI while the sqlcommand is being executed.

--
John Wood
EMail: first name, dot, second name at priorganize.com
"Michael C" <mi*******@opto nline.net> wrote in message
news:g_******** **************@ news4.srv.hcvln y.cv.net...

Thanks for the link. He has the same example code in his book (Windows
Forms Programming in C#). Problem is that it doesn't solve my real problem, which is that the SQL Query I'm executing seems to block the Timer() control Tick event from ever executing. Even when I run the status update code on a separate thread like in his book... How can I make my Timer() Tick like
it's supposed to?

Thanks,
Michael C.

"Miha Markic [MVP C#]" <miha at rthand com> wrote in message
news:up******** ******@tk2msftn gp13.phx.gbl...

Hi Michael,

See this fine article (there are 3 parts)
Safe, Simple Multithreading in Windows Forms

http://msdn.microsoft.com/library/de...ms06112002.asp

--
Miha Markic [MVP C#] - RightHand .NET consulting & development
miha at rthand com
www.rthand.com

"Michael C" <mi*******@opto nline.net> wrote in message
news:y2******** **************@ news4.srv.hcvln y.cv.net...

Hi all,

I'm now trying to update a status indicator via a Timer control on a

worker

thread. The status indicator is just a label on the main form, but I'm having trouble figuring out exactly how to implement a separate worker
thread or asynchronous delegate that changes the label contents based

on

the

Timer control's ticks. Are there any good examples out there and can

you point me to one or two?

Thanks,
Michael C.

Yeah I have a 'not-so-elegant' solution I'm playing with now. I had to use
a Timer from the System.Timers namespace as opposed to the Windows.Forms
timer and then execute the SQL Queries in asynchronous delegates using
callbacks. You'd think there'd be an easier way. I'm sure there's a better
way. It's amazing that something so simple could be so complicated to
implement.

Thanks,
Michael C.

"John Wood" <sp**@isannoyin g.com> wrote in message
news:uL******** ******@tk2msftn gp13.phx.gbl...

Any timers added in the UI (through the Timer control) require that the
message queue is being pumped in the UI thread for the timer to execute. If you have executed a synchronous procedure on the UI thread, then the UI
thread will be blocked until the function returns and the timer will not
execute.

You might find that it's better to execute the sqlcommand on a worker thread (the easiest way is through the thread pool), leaving you free to update the UI while the sqlcommand is being executed.

--
John Wood
EMail: first name, dot, second name at priorganize.com
"Michael C" <mi*******@opto nline.net> wrote in message
news:g_******** **************@ news4.srv.hcvln y.cv.net...

Thanks for the link. He has the same example code in his book (Windows
Forms Programming in C#). Problem is that it doesn't solve my real problem,

which is that the SQL Query I'm executing seems to block the Timer()

control

Tick event from ever executing. Even when I run the status update code on a

separate thread like in his book... How can I make my Timer() Tick like
it's supposed to?

Thanks,
Michael C.

"Miha Markic [MVP C#]" <miha at rthand com> wrote in message
news:up******** ******@tk2msftn gp13.phx.gbl...

Hi Michael,

See this fine article (there are 3 parts)
Safe, Simple Multithreading in Windows Forms

http://msdn.microsoft.com/library/de...ms06112002.asp

--
Miha Markic [MVP C#] - RightHand .NET consulting & development
miha at rthand com
www.rthand.com

"Michael C" <mi*******@opto nline.net> wrote in message
news:y2******** **************@ news4.srv.hcvln y.cv.net...
> Hi all,
>
> I'm now trying to update a status indicator via a Timer control on a
worker
> thread. The status indicator is just a label on the main form, but I'm > having trouble figuring out exactly how to implement a separate worker > thread or asynchronous delegate that changes the label contents

based on the
> Timer control's ticks. Are there any good examples out there and

can you

> point me to one or two?
>
> Thanks,
> Michael C.
>
>

Yeah you would think it would be easier I know. ADO.Net isn't exactly the
holy grail it's often made out to be.

Keep in mind that so-called 'asynchronous delegates' may be asynchronous,
but they simply execute on a temporary worker thread taken from the thread
pool. There 2 problems with this. Firstly, the thread pool has a limit of 64
threads, if more than that are in use, the operation will be queued until a
thread slot is availble. Secondly, it's unnecessary -- these sql operations
are asynchronous in nature (ie. they send data over sockets, and then wait
for the response from the server). It's unnecessary to have a thread
dedicated to waiting for the data to come back when it could just have the
socket send a message to the UI when the data is available. All of the async
mechanisms in .net use the thread-pool, even web-requests. All seems a bit
silly if you ask me.

--
John Wood
EMail: first name, dot, second name at priorganize.com
"Michael C" <mi*******@opto nline.net> wrote in message
news:q_******** **************@ news4.srv.hcvln y.cv.net...

Yeah I have a 'not-so-elegant' solution I'm playing with now. I had to use a Timer from the System.Timers namespace as opposed to the Windows.Forms
timer and then execute the SQL Queries in asynchronous delegates using
callbacks. You'd think there'd be an easier way. I'm sure there's a better way. It's amazing that something so simple could be so complicated to
implement.

Thanks,
Michael C.

"John Wood" <sp**@isannoyin g.com> wrote in message
news:uL******** ******@tk2msftn gp13.phx.gbl...

Any timers added in the UI (through the Timer control) require that the
message queue is being pumped in the UI thread for the timer to execute. If

you have executed a synchronous procedure on the UI thread, then the UI
thread will be blocked until the function returns and the timer will not
execute.

You might find that it's better to execute the sqlcommand on a worker

thread

(the easiest way is through the thread pool), leaving you free to update

the

UI while the sqlcommand is being executed.

--
John Wood
EMail: first name, dot, second name at priorganize.com
"Michael C" <mi*******@opto nline.net> wrote in message
news:g_******** **************@ news4.srv.hcvln y.cv.net...

Thanks for the link. He has the same example code in his book (Windows Forms Programming in C#). Problem is that it doesn't solve my real

problem,

which is that the SQL Query I'm executing seems to block the Timer()

control

Tick event from ever executing. Even when I run the status update code on

a

separate thread like in his book... How can I make my Timer() Tick

like it's supposed to?

Thanks,
Michael C.

"Miha Markic [MVP C#]" <miha at rthand com> wrote in message
news:up******** ******@tk2msftn gp13.phx.gbl...
> Hi Michael,
>
> See this fine article (there are 3 parts)
> Safe, Simple Multithreading in Windows Forms
>

http://msdn.microsoft.com/library/de...ms06112002.asp

>
> --
> Miha Markic [MVP C#] - RightHand .NET consulting & development
> miha at rthand com
> www.rthand.com
>
> "Michael C" <mi*******@opto nline.net> wrote in message
> news:y2******** **************@ news4.srv.hcvln y.cv.net...
> > Hi all,
> >
> > I'm now trying to update a status indicator via a Timer control on a > worker
> > thread. The status indicator is just a label on the main form,

but

I'm

> > having trouble figuring out exactly how to implement a separate

worker > > thread or asynchronous delegate that changes the label contents based

on

> the
> > Timer control's ticks. Are there any good examples out there and

can you
> > point me to one or two?
> >
> > Thanks,
> > Michael C.
> >
> >
>
>

I am a little disappointed that there's no built-in simple (50 words or
less) way to update the UI from a worker thread. I would think this would
be a very common problem that programmers run up against all the time. As
for the SQL operations running asynchronously, for whatever reason (maybe
because I'm running them on a local SQL Server??) the SqlCommands I'm
sending are completely blocking the Windows Forms.Timer() control. I've
verified that it doesn't Tick at all until the SqlCommand has finished
executing. I thought the SqlCommands ran asynchronously also, but it
doesn't look like it; or maybe there's an asynchronous option on the
SqlCommand I'm missing? As far as the limits on the thread pool, that
shouldn't be a problem. The only two things I'm doing at any one time are:
1) running one SqlCommand at a time and 2) updating the status on the UI.
Other than that, all other processing occurs in the UI thread.

Thanks for the help!

Michael C.

"John Wood" <sp**@isannoyin g.com> wrote in message
news:O5******** ******@tk2msftn gp13.phx.gbl...

Yeah you would think it would be easier I know. ADO.Net isn't exactly the
holy grail it's often made out to be.

Keep in mind that so-called 'asynchronous delegates' may be asynchronous,
but they simply execute on a temporary worker thread taken from the thread
pool. There 2 problems with this. Firstly, the thread pool has a limit of 64 threads, if more than that are in use, the operation will be queued until a thread slot is availble. Secondly, it's unnecessary -- these sql operations are asynchronous in nature (ie. they send data over sockets, and then wait
for the response from the server). It's unnecessary to have a thread
dedicated to waiting for the data to come back when it could just have the
socket send a message to the UI when the data is available. All of the async mechanisms in .net use the thread-pool, even web-requests. All seems a bit
silly if you ask me.

--
John Wood
EMail: first name, dot, second name at priorganize.com

"Michael C" <mi*******@opto nline.net> wrote in message
news:g_******** **************@ news4.srv.hcvln y.cv.net...

Thanks for the link. He has the same example code in his book (Windows
Forms Programming in C#). Problem is that it doesn't solve my real problem, which is that the SQL Query I'm executing seems to block the Timer() control Tick event from ever executing. Even when I run the status update code on a separate thread like in his book... How can I make my Timer() Tick like
it's supposed to?

If your seperate thread is not responding to Timer events (or any other),
run the thread continuously in a loop and use Thread.Sleep() so as to not
consume the processor.

Norvin