[VB.net] - Dealing with First Chance Exceptions

[zubair1]

Hi,

Today, i added some new code which was to see if a file is locked or not (in use by another application). While i did that it was showing me some errors like in the Output window:-

A first chance exception of type 'System.UnauthorizedAccessException' occurred in Microsoft.VisualBasic.dll
A first chance exception of type 'System.UnauthorizedAccessException' occurred in Microsoft.VisualBasic.dll
A first chance exception of type 'System.UnauthorizedAccessException' occurred in Microsoft.VisualBasic.dll
A first chance exception of type 'System.IO.IOException' occurred in Microsoft.VisualBasic.dll
A first chance exception of type 'System.IO.IOException' occurred in Microsoft.VisualBasic.dll
A first chance exception of type 'System.IO.IOException' occurred in Microsoft.VisualBasic.dll
A first chance exception of type 'System.UnauthorizedAccessException' occurred in Microsoft.VisualBasic.dll

Can some help and tell me if this is any serious problem, after searching for a while and reading very confusing articals i couldn't understand if it is or not - if i understand correctly what they meant they said it wasn't important and i should ignore these messages?

Thanks in advance
Regards

[balabaster]

Check out this article about first chance exceptions, it may be useful:

http://social.msdn.microsoft.com/Forums/en-US/netfxbcl/thread/da1eedcd-50d3-46b0-bfd8-f3c840d72b55/

[zubair1]

Check out this article about first chance exceptions, it may be useful:

http://social.msdn.microsoft.com/For...-f3c840d72b55/

Thanks, it was pretty useful.

I think i understand it alittle but just not sure if i should ignore these..

The post you pointed to sort of makes the same suggestion but says it really depeneds on the application :s i got those exceptions when i was trying to see if a file is opened by trying to write in it or delete it.

[balabaster]

Thanks, it was pretty useful.

I think i understand it alittle but just not sure if i should ignore these..

The post you pointed to sort of makes the same suggestion but says it really depeneds on the application :s i got those exceptions when i was trying to see if a file is opened by trying to write in it or delete it.

In my experience they can mostly be ignored, but personally I can't stand leaving unhandled exceptions in my code, even if they are outwardly harmless.

[zubair1]

Thanks :)

Do you think i should i worry about these messages that i am getting then?

They are not unhandled right?


Regards

[balabaster]

Thanks :)

Do you think i should i worry about these messages that i am getting then?

They are not unhandled right?


Regards

Well theoretically, they occur because you have a method that throws an exception that may or may not be handled. It is a second chance exception that causes your application to crash. So you will always encounter first chance exceptions - if you are handling them, you can ignore them.

[zubair1]

Well theoretically, they occur because you have a method that throws an exception that may or may not be handled. It is a second chance exception that causes your application to crash. So you will always encounter first chance exceptions - if you are handling them, you can ignore them.

ahhh oh ok great, thanks alot :)