c＃应用程序遇到问题并且没有明显原因关闭。 第三方dll可能存在的问题

Question

We're building ac# application which will sit on PC's in garbage trucks. Things work fine on our development machines but as always, problems start to arise when we deploy onto our target hardware.

One in particular is giving us headaches. At random intervals we will get a windows message box popping up and saying that our application has encountered a problem and needs to be closed.

The application still works fine while the dialog box is sitting there, and obviously it closes when you click the close button. The frustrating thing is we get no exceptions, nothing in any logs, nothing in the system activity log. My hunch that there's some problem happening in a 3rd party library which we are using for GPS, which is a .net wrapper for an unmanaged dll which we've had problems with before. What options do we have to try and debug this?? I'm relatively new to windows programming and wondering if there are programs we can use to track which parts of a dll are being called by our code.

Cheers Nimai

Answer 1

I feel for ya, these things are very hard to debug when its likely to be a problem in the 3rd party native dll itself.

What you could do in the meanwhile to make your app a little more robust is to load up your Wrapper assembly into a dynamically loaded App Domain instead of straight into your app, that way the DLL will just bring down the app domain not your whole app. You can then have some code to restart (the app domain) if required. Note this is not fixing your problem, but at least making the app a little more robust in the field.

Note there are some hoops to jump through in terms of marshalling data between your app domains, but nothing too onerous.

Edit: Here is a nice blog post that supplies a sample

Answer 2

• Have you added a thread exception handler?
• Are you logging exceptions?
• What type of error handling do you have?
• What does the message box say (Title and text)?
• Is this a WinForms application?
• Is the GPS component COM based? If so, ensure valid arguments are being passed to it's functions.
• Is this a Win32 exception? (Does the message box say "Win32 exception")
• Is this a COM exception?
• Are you running a timer in your application that triggers the GPS component calls?
• Are you running any type of timer in your application?

Answer 3

Try logging all exceptions

    static void Main(string[] args)
    {
        Application.ThreadException += ApplicationThreadException;
        AppDomain.CurrentDomain.UnhandledException += CurrentDomainUnhandledException;

        //Your code would go here
        throw new Exception("a");
    }

    static void ApplicationThreadException(object sender, ThreadExceptionEventArgs e)
    {
        LogException(e.Exception);
    }
    static void CurrentDomainUnhandledException(object sender, UnhandledExceptionEventArgs e)
    {
        LogException(e.ExceptionObject);
    }

    private static void LogException(object exception)
    {
        //you could of course log anywhere
        EventLog.WriteEntry("ConsoleApplication1", exception.ToString(), EventLogEntryType.Error);
    }