developer.* Blogs - .NET BackgroundWorker Mysteries Solved - Comments

Backgroundworker returned result

Kostas — Fri, 12 Jan 2007 04:06:04 -0800

I am trying to return as a result an array of bytes,
I am always getting an exception thread about overflow if I try to return saying more than 510 bytes. Is there a maximum allowable number for the
e.result object?

/Kostas

Thanks for this post ! I was

FAS — Sat, 30 Dec 2006 07:01:27 -0800

Thanks for this post ! I was stuck with this "error-handling" issue.

One solution is to use a

bill xie — Thu, 21 Dec 2006 13:35:40 -0800

One solution is to use a class to return your result instead of using simple types

Good points: Now try this one on for size

Guest — Tue, 19 Dec 2006 05:38:19 -0800

Hi Daniel,

These are all good points, and I came across most of them myself in the last few days. So far so good, but now I'm really stuck. I've implemented M-V-P and got the Backgroundworker passed down to the Presenter (also tried creating it there instead), and the background code fetches user history from the DB async. Fantastic! Now I'm trying to unit test this logic to get the code coverage up. Something I've found particularly frustrating is that the TestMethod (NUnit) makes the call to getUserHistory() in the presenter which hits the DoWork delegate just fine on another thread, but then the RunWorkerComplete event never fires, even though I've subscribed to it from the TestMethod and put a while loop holding the main thread alive for 30 seconds. Do you know how I can unit test this BackgroundWorker, or am I going to have to manage my own thread pool like I've always done?

Any help appreciated....
Thanks,
Rob

background woker thread issue

deloford — Wed, 13 Dec 2006 04:23:17 -0800

Not being able to use try{}catch is really frustrating, I have a BackgroundWorker thread processing a list of jobs, jobs may throw exceptions, but I need to continue on to the next job, how do I achieve this now, I have to create another background worker or restart from the correct place everytime there is an exception?

.NET BackgroundWorker Mysteries Solved

Daniel Read — Mon, 04 Dec 2006 09:48:29 -0800

I've found the BackgroundWorker to be very handy, but a little tricky to start using at first. I like that it has built-in support for reporting incremental progress for a long-running operation, and that it has a simple way of allowing a long-running operation to be canceled. And the big benefit, of course, is that your form remains responsive to the user and the operating system as it runs on the main UI thread. But there are some subtleties I had to overcome that are not covered in the documentation, especially in the area of exception handling.