[.Net 1.1] Strange error

Hello

I have a scrollable System.Windows.Forms.Panel, and I add/remove
controls (ListView only) to/from it programatically.

Sometimes, probaly when redrawing the panel while adding/removing
controls or scrolling the panel i get an infinite loop of messageboxes
saying "invalid parameter used" but no exceprion is thrown. It happens
randomly, I cannot reproduce steps to achieve it.

I do not do any painting operations on it, I handle only few events
related to mouse and SelectedItem in listview.

Wha co I do to avoid it?

--
Semper Fidelis

Adam Klobukowski
atari@gabo.pl

Mehdi
Tue Mar 14 10:02:03 CST 2006

On Tue, 14 Mar 2006 15:54:52 +0100, Adam Klobukowski wrote:

> I have a scrollable System.Windows.Forms.Panel, and I add/remove
> controls (ListView only) to/from it programatically.
>
> Sometimes, probaly when redrawing the panel while adding/removing
> controls or scrolling the panel i get an infinite loop of messageboxes
> saying "invalid parameter used" but no exceprion is thrown. It happens
> randomly, I cannot reproduce steps to achieve it.

None of the methods of the .NET Framework classes display any message box
unless you explicitely ask them to. So you must have some code somewhere
that catches some (or all) of the exceptions and displays a message box
with the exception message instead of letting the exception bubble up. Find
this code and remove that so that you can trace where the problem comes
from.

Or are you talking about Visual Studio's unhandled exception dialog box
that pops up automatically whenever an unhandled exception occurs in your
code? In this case, run your application in Debug mode and when this dialog
box pops up, click the Break button to break into your code. From there,
you'll be able to examine your stack trace and the state of your objects to
determine why the exception has been thrown.

In any case, you can always configure Visual Studio to break into your code
whenever an exception (handled or not) is thrown by going to: Debug menu ->
Exceptions -> Common Language Runtime Exceptions -> When an exception is
thrown: break into the debugger.

Adam
Wed Mar 15 02:13:10 CST 2006

Mehdi napisaÅ?(a):
> On Tue, 14 Mar 2006 15:54:52 +0100, Adam Klobukowski wrote:
>
>> I have a scrollable System.Windows.Forms.Panel, and I add/remove
>> controls (ListView only) to/from it programatically.
>>
>> Sometimes, probaly when redrawing the panel while adding/removing
>> controls or scrolling the panel i get an infinite loop of messageboxes
>> saying "invalid parameter used" but no exceprion is thrown. It happens
>> randomly, I cannot reproduce steps to achieve it.
>
> None of the methods of the .NET Framework classes display any message box
> unless you explicitely ask them to. So you must have some code somewhere
> that catches some (or all) of the exceptions and displays a message box
> with the exception message instead of letting the exception bubble up. Find
> this code and remove that so that you can trace where the problem comes
> from.
>
> Or are you talking about Visual Studio's unhandled exception dialog box
> that pops up automatically whenever an unhandled exception occurs in your
> code? In this case, run your application in Debug mode and when this dialog
> box pops up, click the Break button to break into your code. From there,
> you'll be able to examine your stack trace and the state of your objects to
> determine why the exception has been thrown.
>
> In any case, you can always configure Visual Studio to break into your code
> whenever an exception (handled or not) is thrown by going to: Debug menu ->
> Exceptions -> Common Language Runtime Exceptions -> When an exception is
> thrown: break into the debugger.

The problem is I'm 100% sure that not my code is displaying it - the
strange thing in it is that text in message box is bold. I do not
remember any standart .NET messagebox being able to output bold text.
Moreover, there are 3 MessageBox.Show calls around that code, but all of
them display fixed text.

I know I can catch any exception, but the problem is that it happens
really randomly and when I try to trigger it it just does not happen.

--
Semper Fidelis


Adam Klobukowski
atari@gabo.pl