C# Discussion Boards - CodeProject

Re: simple page load query

Eddy Vluggen17-Apr-09 3:24

Eddy Vluggen

17-Apr-09 3:24

AndyInUK wrote:
yes it is in the same class as Page_Load. it is user control code basically.

Is it part of the page, or part of that user-control? If it's private to the user-control, you won't be able to call it from outside that user-control.

I are troll Smile | :)

Re: simple page load query

Colin Angus Mackay17-Apr-09 5:14

Colin Angus Mackay

17-Apr-09 5:14

Weird... Another message disappears just as I'm replying to it...

AndyInUK wrote:
There are various methods derived in abstract class

That doesn't make any sense.

You derive a class. You override methods. Or you make methods virtual (available for overriding) or abstract (mandatory for overriding)

AndyInUK wrote:
I am unable to find such derived class.

If I knew what you were talking about rather than naming things after sequential groups of letters it might make more sense.

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Reading files

satsumatable17-Apr-09 2:20

satsumatable

17-Apr-09 2:20

Hi,

I'm trying to read a file which is present in remote PC (basically i've created a logical drive in my local system and mapped it) it works well during debug mode but it doesnt work in the release mode (when i install the project).

Do i need to set any permissions? It is C# Windows Application.

Thanks

Re: Reading files

Colin Angus Mackay17-Apr-09 2:22

Colin Angus Mackay

17-Apr-09 2:22

satsumatable wrote:
it doesnt work in the release mode (when i install the project).

How, exactly, does it not work? Does it produce an error? If so what? If not how can you tell it isn't working?

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Re: Reading files

satsumatable17-Apr-09 2:27

satsumatable

17-Apr-09 2:27

It throws an error as like below

It is saying part of the file path is not found.

Re: Reading files

stancrm17-Apr-09 2:29

stancrm

17-Apr-09 2:29

probably you call like "myfile.exe". That means, if you change the directory, then the file is not there anymore.
Try to call using fullname, like "c:\mydir\myfile.exe".

Re: Reading files

stancrm17-Apr-09 2:28

stancrm

17-Apr-09 2:28

use try catch, show the exception message, then you can see what's wrong with your application.

Re: Reading files

satsumatable17-Apr-09 2:31

satsumatable

17-Apr-09 2:31

file path is exactly going like "c:\mydir\myfile.exe"

Re: Reading files

stancrm17-Apr-09 2:36

stancrm

17-Apr-09 2:36

try to show your path+file in a messagebox, just find it, whether the file exists or not.

Re: Reading files

Alan Balkany17-Apr-09 3:42

Alan Balkany

17-Apr-09 3:42

You need to put a '@' before the string to handle the back slashes correctly:

@"c:\mydir\myfile.exe"

A security exception was not handled in your code

lachu00917-Apr-09 2:07

lachu009

17-Apr-09 2:07

Hi,

I got an error "A security exception was not handled in your code" when i try to open a page using server.transfer.But when changed the application server it worked perfectly. what could be the issue? Is it an IIS configuration issue ,Server configuration issue or any other..

Thanks in advance

cross thread operation not valid, when closing a windows form

But_Im_a_Lady17-Apr-09 1:19

But_Im_a_Lady

17-Apr-09 1:19

Hi All,

After spending ages on google trying to understand & recify my problem, and having no success, I am hoping someone here can point me in the right direction.

Here is my problem...

I have a windows form, which has a selection of standard toolbox controls and custom User controls, some of which are added at design time & some of which are added at run time.

This all works fine, but when I close the form I get this message:-

"Cross-thread operation no valid: Control 'chkShowSparesMatrix' accessed from a thread other than the thread it was created on".

This control is a standard MS check box which is added at design time. None of its properties are changed in code, the only event which is acted upon is 'checkedchanged':-

private void chkShowSparesMatrix_CheckedChanged(object sender, EventArgs e)
{
    if (chkShowSparesMatrix.Checked)
    {
        usrSparesMatrix1.IsStandAlone = false;
        usrSparesMatrix1.Visible = true;
    }
    else
    {
        usrSparesMatrix1.IsStandAlone = false;
        usrSparesMatrix1.Visible = false;
    }
}

If I remove this control, I get the same message on another control.

If anyone can throw light on this for me I would be grateful, or if you need more info to understand my problem I can forward you this.

Thanks in advance,

Janet

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

Henry Minute17-Apr-09 1:55

Henry Minute

17-Apr-09 1:55

And are you doing anything in another thread?

Henry Minute

Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”

Re: cross thread operation not valid, when closing a windows form

But_Im_a_Lady17-Apr-09 2:05

But_Im_a_Lady

17-Apr-09 2:05

The only thing I do on another thread is 'faxing', which is subject to the user saying they want to 'fax' a document, so this doesn't always get fired, unless they answer Yes to a series of questions.

I get the error message, regardless of choosing to Fax or not!

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

Henry Minute17-Apr-09 2:12

Henry Minute

17-Apr-09 2:12

Have a look at the link that 12Code gave you. I haven't looked at it, so don't know if it will help. If it doesn't help, feel free to come back.

Re: cross thread operation not valid, when closing a windows form

But_Im_a_Lady17-Apr-09 2:14

But_Im_a_Lady

17-Apr-09 2:14

Thanks - will do

Janet

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

But_Im_a_Lady17-Apr-09 2:25

But_Im_a_Lady

17-Apr-09 2:25

My first step was to comment out all references to 'faxing' (this was the other thread in my form) and I still get this error.

So now I am confused Confused | :confused:

Janet

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

Henry Minute17-Apr-09 2:39

Henry Minute

17-Apr-09 2:39

The only thing that makes any sense is as 12Code said in his OP. Somehow the 'faxing' thread is getting started, and then causes the error when you close the app.

What sort of threading are you using? Is it a BackgroundWorker, or are you creating it in code?

Whichever type, one way might be to handle the FormClosing event of your main form and close/de-activate the thread there.

Re: cross thread operation not valid, when closing a windows form

But_Im_a_Lady17-Apr-09 2:49

But_Im_a_Lady

17-Apr-09 2:49

I am using 'System.Threading', the code is below:-

private void FaxEngineersRequest()
        {
            try
            {
                //SendZetaFax sendZetaFax = new SendZetaFax ();
                //sendZetaFax.FaxBody = _processingModule.CreateEngineerCallSheet ( _callNumber ).ToString ();
                //sendZetaFax.FaxNumber = usrAddressDetailsEngineer.Fax;
                //sendZetaFax.RecipientName = usrAddressDetailsEngineer.Contact;
                //sendZetaFax.From = _sysCNDR.Name;

                ////Since the processing for Zeta fax can be v.slow - do processing on a separate thread.
                //Thread thread = new Thread ( new ThreadStart ( sendZetaFax.SendFaxMessage ) );
                //thread.Start ();
            }
            catch (Exception ex)
            {
                _commonValidation.DisplayErrorGracefully ( ex );
            }
        }

As you can see I have commented this part of the code out - so it will never run, but I still get the cross thread operation not valid error.

<blockquote class="FQ"><div class="FQA">Henry Minute wrote:</div>Whichever type, one way might be to handle the FormClosing event of your main form and close/de-activate the thread there. </blockquote>
Not quite sure how / if / why I need to do this Confused | :confused:

Janet

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

Henry Minute17-Apr-09 2:59

Henry Minute

17-Apr-09 2:59

If your 'faxing' thread does not run, and it certainly shouldn't from the code you posted, then there has to be another thread running to cause the exception.

If you don't know about this thread, you obviously cannot close it in the FormClosing handler. You might however put a break point there and use the debugger to search for the 'Thread With No Name'. I would suggest Googling for 'Debugging Threads C#' for methods to do this.

As always, come back if no joy.

Re: cross thread operation not valid, when closing a windows form

But_Im_a_Lady20-Apr-09 1:16

But_Im_a_Lady

20-Apr-09 1:16

For completeness of this message - I have now fixed my problem.

I made a STUPID D'Oh! | :doh:

mistake...

Rushing to finish the project I had put Close() inside the formclosing event!!!

Won't be doing that again in a hurry Smile | :)

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

12Code17-Apr-09 2:06

12Code

17-Apr-09 2:06

The other thread that you created has directly update the form control, which is not allowed.

You need to use Invoke. I have a thread might help you.
http://www.codeproject.com/script/Forums/View.aspx?fid=1649&select=2972472&tid=2972413#xx2972472xx[^]

*12Code

Re: cross thread operation not valid, when closing a windows form

But_Im_a_Lady17-Apr-09 2:15

But_Im_a_Lady

17-Apr-09 2:15

Thanks - will look at this & try & get it to work.

Janet

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

But_Im_a_Lady17-Apr-09 2:22

But_Im_a_Lady

17-Apr-09 2:22

Just to prove your theory I commented out all references to 'faxing' (this was the other thread in my form) & I still get this error.

So now I am confused Confused | :confused:

Lady Programmers are a rare breed!

Re: cross thread operation not valid, when closing a windows form

0x3c017-Apr-09 2:46

0x3c0

17-Apr-09 2:46

What about the if-clause? Doesn't that access chkShowSparesMatrix?

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