unhandled exception not caught by SA

• 
  Hi,
  
  Here are some ideas:
  
  It could be a clash between your error handling code and the error handling code inserted by SmartAssembly. Is your code still implementing an unhandled exception handler ?
  
  Or it could be related to multiple app domains. Are you using multiple app domains?
  
  Can you throw some simple exceptions elsewhere in your code ? Are any of these reported correctly ?
  
  Is it possible you are using a build script which uses an older saproj that does not have error reporting turned on.

  james.davies January 18, 2012 10:48

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  james.davies wrote:

  Hi,
  
  Here are some ideas:
  
  It could be a clash between your error handling code and the error handling code inserted by SmartAssembly. Is your code still implementing an unhandled exception handler ?

  We did have a very basic one in the earlier stages of the migration, as a placeholder for when we were still considering doing our own error reporting system, but this has all been removed from the project now.
  

  Or it could be related to multiple app domains. Are you using multiple app domains?

  Not intentionally. Is there anything in the .NET framework classes used to support code migrated from VB6 that could be doing so behind the scenes?

  Can you throw some simple exceptions elsewhere in your code ? Are any of these reported correctly ?

  I just added one right at the beginning of the Main() method and it was handled correctly. I will try adding more around the area where it is not reporting them correctly to see if that provides any more clues as to what is going awry.

  Is it possible you are using a build script which uses an older saproj that does not have error reporting turned on.

  No, we're not using a build script yet. I'm still using the tools interactively at this stage.

  JDHnz January 18, 2012 16:15

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  james.davies wrote:

  Or it could be related to multiple app domains. Are you using multiple app domains?

  While I'm fairly certain that we're not using multiple app domains, we might be doing something a little different with the message loop from the standard Winforms app, by having multiple calls to System.Windows.Forms.Application.Run() for when we have different forms as the main window of the app at different stages.
  
  Our app runs something like this:

  Sub Main
      fSplash = New frmSplash
      fSplash.Show()
  
      ' program initialisation code goes here (open DB connection, etc.)
  
      System.Windows.Forms.Application.Run(fSplash)
  
      Do While fSplash.IsLoggedIn
          fSplash = Nothing
  
          fMDI = New frmMDI
          System.Windows.Forms.Application.Run(fMDI)
  
          If fMDI.IsExitingApp Then Exit Do
          fMDI = Nothing
  
          fSplash = New frmSplash
          fSplash.Show()
          System.Windows.Forms.Application.Run(fSplash)
      Loop
  End Sub
  

  My experiments showed that any exceptions thrown before the call to System.Windows.Forms.Application.Run(fMDI) would be caught by the SA UnhandledException handler, but after that they would be dealt with by the default Winforms handler.

  JDHnz January 18, 2012 20:28

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• 
  I have created a minimal project that reproduces the problem I have encountered. It can be downloaded from here.
  
  You will notice that a click on the Throw Exception button on the "Splash" form, the first time it is opened, results in the standard SmartAssembly error window popping up, but a click on the Throw Exception menu item in the MDI or a click on the Throw Exception button on the Splash window after logging in and back out again, results in the default Windows Forms exception window.

  JDHnz January 23, 2012 18:18

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  Error reporting uses the standard application message loop.
  
  It seems that extra calls to Application.Run() cause a problem with this.
  
  It could be that calls to Application.Run() start a new message loop and SA is hooked into the old one causing the exceptions to not be reported.
  
  Thanks for the reproduction of the problem. I will add this to our bug tracking system and see what the developers say.

  james.davies January 25, 2012 11:44

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  Has any progress been made on getting SA to cope with this scenario?

  JDHnz February 07, 2012 15:27

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  [bump] Anything?

  JDHnz February 20, 2012 05:09

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  There are no comments yet from the developers on this bug. I will try to get them to take a look.

  james.davies February 21, 2012 09:58

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• 
  (Have heard from developer regarding this:)
  
  This problem is because the current thread context (which is where the unhandled exception handler gets attached) is completely removed at the end of the Application.Run method.
  
  Please use Form.Show instead of Application.Run - http://social.msdn.microsoft.com/Forums/en-us/winforms/thread/aead5e9a-2e06-4adf-aecc-f45a2a633768

  james.davies February 24, 2012 06:22

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