How process messages in a loop?

[Bill]

I am copying data from one FileStream to another in a loop. Inside the
loop I display progress messages in a StatusBar. The form has a Stop
button that sets a private Boolean variable to true. Also inside the
loop I check that value of the variable and exit the loop if it is true.

I have two problems. First, clicking the Stop button has no effect.
It's Click event handler does not execute. Second, if I drag the form
to a different location on the screen the progress messages stop
displaying even though I call StatusBar.Refresh in the loop.

What should I call in the loop to allow messages and events to be
processed?

--
..Bill.

[Jon Skeet [C# MVP]]

Bill <[e-mail]> wrote:

I am copying data from one FileStream to another in a loop. Inside the
loop I display progress messages in a StatusBar. The form has a Stop
button that sets a private Boolean variable to true. Also inside the
loop I check that value of the variable and exit the loop if it is true.

I have two problems. First, clicking the Stop button has no effect.
It's Click event handler does not execute. Second, if I drag the form
to a different location on the screen the progress messages stop
displaying even though I call StatusBar.Refresh in the loop.

What should I call in the loop to allow messages and events to be
processed?

You shouldn't. Instead, you should do the processing in a different
thread, crossing back to the UI thread to update the UI with progress.

See http://www.pobox.com/~skeet/csharp/t...winforms.shtml

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[Morten Wennevik]

Hi Bill,

As Jon said, you should use another thread for processing and keep the UI thread free. However, there is a way that will accomplish what you seek (for short tiny applications :). Calling Application.DoEvents() will process pending events.
On Sun, 24 Jul 2005 22:49:47 +0200, Bill <[e-mail]> wrote:

I am copying data from one FileStream to another in a loop. Inside the
loop I display progress messages in a StatusBar. The form has a Stop
button that sets a private Boolean variable to true. Also inside the
loop I check that value of the variable and exit the loop if it is true.

I have two problems. First, clicking the Stop button has no effect.
It's Click event handler does not execute. Second, if I drag the form
to a different location on the screen the progress messages stop
displaying even though I call StatusBar.Refresh in the loop.

What should I call in the loop to allow messages and events to be
processed?

--
Happy coding!
Morten Wennevik [C# MVP]

[Bill]

Thanks guys. Application.DoEvents will solve my immidiate problem. I
will rewrite this using threads since I need to learn how to use
threads anyway.

--
..Bill.