Unrepeatable form bugs -- Is 100% managed .Net Stable?

I am getting the following UNREPEATBLE symptoms on my 100% managed
application:-

- Form will not close via window close button. Need to Application.Exit().
- Keyboard events lost, cannot access the menus with Alt-
- Null pointer exceptions deep within the Windows runtime.
- TextBox OnValidated events stop firing after a while. OnLeave still
works.

Something is destabalizing the entire system. Feels like the bad old days
of C++, eg. a corruped pointer. But that should not happen in .Net. Has
anyone had similar problems?

The application is very simple, with only one main form, only one thread.
One complication is that it uses a Model-View-Controller approach and if the
model changes too much I just recreate the guts of the form from scratch.

The form has a TabControl which is permanent. But I periodically
TabControl.Clear() and then recreate all the tab pages. I have not bothered
removing the individual controls on the page before the .Clear(), I would
expect this to recurse automatically.

I have created a small dummy TextBox on the main form, and I send the focus
their before doing a Clear. This seems to reduce the crashes. But one
problem -- the textbox sometimes refuses to accept focus for no apparent
reason.

This is worrying. One can waste a lot of time hacking around buggy systems
changing things in the hope that the bugs will disapear. Not having the
.Net sources is also a worry -- I don't want to have to read them but in the
event of a crash they are handy. Maybe we should have used Java.

Regards,

Anthony

Anthony
Wed Aug 06 16:53:58 CDT 2003

These type of unrepeatable bugs are scary because they can be very difficult
to track down and so kill an otherwise good project. I would be very
interested to know if anyone else has experienced them. I suspect problems
with all the internal unmanaged code interation in .Net. Garbage collection
can make unmanaged coding bugs extremely difficult to track down.

Is .Net stable?

Anthony

"Anthony Berglas" <aberglas at frontsys (a spam free .com)> wrote in message
news:3f2b24cf$1_1@news.greatbasin.net...
> I am getting the following UNREPEATBLE symptoms on my 100% managed
> application:-
>
> - Form will not close via window close button. Need to
Application.Exit().
> - Keyboard events lost, cannot access the menus with Alt-
> - Null pointer exceptions deep within the Windows runtime.
> - TextBox OnValidated events stop firing after a while. OnLeave still
> works.
>
> Something is destabalizing the entire system. Feels like the bad old days
> of C++, eg. a corruped pointer. But that should not happen in .Net. Has
> anyone had similar problems?
>
> The application is very simple, with only one main form, only one thread.
> One complication is that it uses a Model-View-Controller approach and if
the
> model changes too much I just recreate the guts of the form from scratch.
>
> The form has a TabControl which is permanent. But I periodically
> TabControl.Clear() and then recreate all the tab pages. I have not
bothered
> removing the individual controls on the page before the .Clear(), I would
> expect this to recurse automatically.
>
> I have created a small dummy TextBox on the main form, and I send the
focus
> their before doing a Clear. This seems to reduce the crashes. But one
> problem -- the textbox sometimes refuses to accept focus for no apparent
> reason.
>
> This is worrying. One can waste a lot of time hacking around buggy
systems
> changing things in the hope that the bugs will disapear. Not having the
> .Net sources is also a worry -- I don't want to have to read them but in
the
> event of a crash they are handy. Maybe we should have used Java.
>
> Regards,
>
> Anthony
>
>