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AnswerRe: Data source selection for C# win app Pin
Dr.Walt Fair, PE13-Aug-10 5:02
professionalDr.Walt Fair, PE13-Aug-10 5:02 
AnswerRe: Data source selection for C# win app Pin
Dan Mos13-Aug-10 7:35
Dan Mos13-Aug-10 7:35 
Questionsplit issue Pin
varsh1213-Aug-10 2:03
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AnswerRe: split issue Pin
Luc Pattyn13-Aug-10 2:08
sitebuilderLuc Pattyn13-Aug-10 2:08 
AnswerRe: split issue Pin
Ian Shlasko13-Aug-10 2:58
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GeneralRe: split issue Pin
Luc Pattyn13-Aug-10 3:38
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GeneralRe: split issue Pin
Ian Shlasko13-Aug-10 4:25
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QuestionUnmanaged callback, Dispose issue Pin
DaveyM6912-Aug-10 23:04
professionalDaveyM6912-Aug-10 23:04 
I've been battling with this issue for a long time and have yet to find a solution that is reliable.

This is the basic flow.
UnmanagedResource.Open(delegate callback);
...
callback called with Opened message
...
... // app does interesting stuff
...

UnmanagedResource.Close(); // will return immediately
...
callback called with Closed message

The problem I have is this. If Close isn't called by the consumer before ending the app then nasty Earth ending stuff can happen. I can of course use the dispose pattern to call Close automatically and I have implemented just that.

This still leaves an issue with the callback though as there is no mechanism on the unmanaged side to unregister from this so the callback will happen but the managed delegate/class instance may no longer be valid when it does.

Is there a method of keeping a class/delegate instance alive inside a Dispose called from a finalizer until a specific callback has happened? Perhaps a blocking loop in Dispose that checks a value that is set in the callback. If this is viable, what is the best way to implement this as depending on the system, the callback may occur on the same or a different thread (I'm no threading expert!).
Dave

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Binging is like googling, it just feels dirtier.
Please take your VB.NET out of our nice case sensitive forum.(Pete O'Hanlon)

BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)

AnswerRe: Unmanaged callback, Dispose issue Pin
Luc Pattyn13-Aug-10 1:51
sitebuilderLuc Pattyn13-Aug-10 1:51 
GeneralRe: Unmanaged callback, Dispose issue Pin
DaveyM6913-Aug-10 2:17
professionalDaveyM6913-Aug-10 2:17 
AnswerRe: Unmanaged callback, Dispose issue Pin
Luc Pattyn13-Aug-10 2:46
sitebuilderLuc Pattyn13-Aug-10 2:46 
GeneralRe: Unmanaged callback, Dispose issue Pin
DaveyM6913-Aug-10 4:35
professionalDaveyM6913-Aug-10 4:35 
GeneralRe: Unmanaged callback, Dispose issue Pin
DaveyM6914-Aug-10 8:30
professionalDaveyM6914-Aug-10 8:30 
GeneralRe: Unmanaged callback, Dispose issue Pin
Luc Pattyn14-Aug-10 8:43
sitebuilderLuc Pattyn14-Aug-10 8:43 
GeneralRe: Unmanaged callback, Dispose issue Pin
DaveyM6914-Aug-10 9:07
professionalDaveyM6914-Aug-10 9:07 
GeneralRe: Unmanaged callback, Dispose issue Pin
Luc Pattyn14-Aug-10 9:19
sitebuilderLuc Pattyn14-Aug-10 9:19 
GeneralRe: Unmanaged callback, Dispose issue Pin
DaveyM6914-Aug-10 9:31
professionalDaveyM6914-Aug-10 9:31 
Questionhow to session value in a page. Pin
Mubeen.asim12-Aug-10 21:38
Mubeen.asim12-Aug-10 21:38 
AnswerRe: how to session value in a page. Pin
Jens Meyer12-Aug-10 22:10
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GeneralRe: how to session value in a page. Pin
Mubeen.asim12-Aug-10 23:17
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QuestionResize problem for drawn rectangle on the picture box? Pin
Nivas8212-Aug-10 20:27
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AnswerRe: Resize problem for drawn rectangle on the picture box? Pin
Luc Pattyn13-Aug-10 2:05
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GeneralRe: Resize problem for drawn rectangle on the picture box? Pin
Nivas8217-Aug-10 20:30
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GeneralRe: Resize problem for drawn rectangle on the picture box? Pin
Luc Pattyn18-Aug-10 1:41
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GeneralRe: Resize problem for drawn rectangle on the picture box? Pin
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