"joseph_gallag***@hotmail.com" wrote:

> Hi,
>
> I have a shoddily written application that is written in 1.1 that I've
> ported to 2.0 and now occasionaly I get crashes which I suspect are
> been caused by exceptions in threads, most likely due to trying to
> access controls which is now stricter, I know I could just set
>
> CheckForIllegalCrossThreadCalls = false;
>
> But I'd rather like to understand a bit better about ways to handle
> these exceptions and diagnose them so have been playing with
> "Application.ThreadException" and
> "AppDomain.CurrentDomain.UnhandledException", the problem I have is
> "Application.ThreadException" never seems to fire and this is cunfusing
> the hell out of me. I have the following simple test code
>
> using System;
> using System.Collections.Generic;
> using System.ComponentModel;
> using System.Data;
> using System.Drawing;
> using System.Text;
> using System.Threading;
> using System.Windows.Forms;
>
> namespace TestApp {
>     public partial class Form1 : Form {
>         public Form1() {
>             InitializeComponent();
>             Application.ThreadException += new
> ThreadExceptionEventHandler(Application_ThreadException);
>             AppDomain.CurrentDomain.UnhandledException += new
> UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
>         }
>
>         void CurrentDomain_UnhandledException(object sender,
> UnhandledExceptionEventArgs e) {
>             MessageBox.Show("CurrentDomain_UnhandledException " +
> e.ExceptionObject.ToString());
>
>         }
>
>         void Application_ThreadException(object sender,
> ThreadExceptionEventArgs e) {
>             MessageBox.Show("Application_ThreadException");
>         }
>
>         private void exceptionButton_Click(object sender, EventArgs e)
> {
>             Thread t = new Thread(delegate() {
>                 int zero = 0;
>                 int x = 1 / zero;
>             });
>             t.IsBackground = true;
>             t.Start();
>         }
>
>         private void crossThread_Click(object sender, EventArgs e) {
>             Thread t = new Thread(delegate() {
>                 crossThread.Text = "Error";
>             });
>             t.IsBackground = true;
>             t.Start();
>         }
>     }
> }
>
> Which is just a windows form that has 2 buttons, crossThreadButton &
> exceptionButton, crossThreadButton simply creates a thread that tries
> to access a control it shouldn't, and exceptionButton simply divides by
> 0 to create a exception, both cause the
> "AppDomain.CurrentDomain.UnhandledException" event to be fired, but
> niether cause the "Application.ThreadException" event to be fired which
> is confusing me.
>
> When should "Application.ThreadException" get called, am I missing a
> setting or is it only for specific situations.
>
> Also is there a way to prevent the application from exiting when there
> is a exception in a thread and
> "AppDomain.CurrentDomain.UnhandledException" is fired, In my main
> shoddy app I'm 99.99% sure that exceptions in threads that have a long
> lifetime are handled and that these problems are been caused in
> shortlived threads that if they fail the work will simply be picked up
> on the next iteration, there is a reasonable amount of manual work
> involved in setting up and configuring the app and loosing all this is
> a pain for the user, if they could be informed of the error but allowed
> to continue that would be a lot easier for me while I find all the
> causes of the problem.
>
>

news:1163592480.983395.172350@h54g2000cwb.googlegroups.com...
> Hi,
>
> I have a shoddily written application that is written in 1.1 that I've
> ported to 2.0 and now occasionaly I get crashes which I suspect are
> been caused by exceptions in threads, most likely due to trying to
> access controls which is now stricter, I know I could just set
>
> CheckForIllegalCrossThreadCalls = false;
>
> But I'd rather like to understand a bit better about ways to handle
> these exceptions and diagnose them so have been playing with
> "Application.ThreadException" and
> "AppDomain.CurrentDomain.UnhandledException", the problem I have is
> "Application.ThreadException" never seems to fire and this is cunfusing
> the hell out of me. I have the following simple test code
>
> using System;
> using System.Collections.Generic;
> using System.ComponentModel;
> using System.Data;
> using System.Drawing;
> using System.Text;
> using System.Threading;
> using System.Windows.Forms;
>
> namespace TestApp {
>    public partial class Form1 : Form {
>        public Form1() {
>            InitializeComponent();
>            Application.ThreadException += new
> ThreadExceptionEventHandler(Application_ThreadException);
>            AppDomain.CurrentDomain.UnhandledException += new
> UnhandledExceptionEventHandler(CurrentDomain_UnhandledException);
>        }
>
>        void CurrentDomain_UnhandledException(object sender,
> UnhandledExceptionEventArgs e) {
>            MessageBox.Show("CurrentDomain_UnhandledException " +
> e.ExceptionObject.ToString());
>
>        }
>
>        void Application_ThreadException(object sender,
> ThreadExceptionEventArgs e) {
>            MessageBox.Show("Application_ThreadException");
>        }
>
>        private void exceptionButton_Click(object sender, EventArgs e)
> {
>            Thread t = new Thread(delegate() {
>                int zero = 0;
>                int x = 1 / zero;
>            });
>            t.IsBackground = true;
>            t.Start();
>        }
>
>        private void crossThread_Click(object sender, EventArgs e) {
>            Thread t = new Thread(delegate() {
>                crossThread.Text = "Error";
>            });
>            t.IsBackground = true;
>            t.Start();
>        }
>    }
> }
>
> Which is just a windows form that has 2 buttons, crossThreadButton &
> exceptionButton, crossThreadButton simply creates a thread that tries
> to access a control it shouldn't, and exceptionButton simply divides by
> 0 to create a exception, both cause the
> "AppDomain.CurrentDomain.UnhandledException" event to be fired, but
> niether cause the "Application.ThreadException" event to be fired which
> is confusing me.
>
> When should "Application.ThreadException" get called, am I missing a
> setting or is it only for specific situations.
>
> Also is there a way to prevent the application from exiting when there
> is a exception in a thread and
> "AppDomain.CurrentDomain.UnhandledException" is fired, In my main
> shoddy app I'm 99.99% sure that exceptions in threads that have a long
> lifetime are handled and that these problems are been caused in
> shortlived threads that if they fail the work will simply be picked up
> on the next iteration, there is a reasonable amount of manual work
> involved in setting up and configuring the app and loosing all this is
> a pain for the user, if they could be informed of the error but allowed
> to continue that would be a lot easier for me while I find all the
> causes of the problem.
>