Stop thread from working (Downloading)

[kill4]

Ok guys, I need some guidance on how i would properly stop a thread from downloading, if a timeout supplied by the user has elapsed.
I have an array threads declared in the general area of the main form class. looks like this.

Private objThreads(100) As Thread

I start these threads in a for loop in a sub routine. I also start an array of timers, that will dictate when these threads should stop working, meaning a certian amount of time has passed. The question is how would i go about stopping these threads from downloading any more data safely? Without disposing of these threads completly. Since i will restart these threads again to do more work.. Any ideas guys?

Thanks..

 

[jmcilhinney]

That's not the way you should go about it. Creating 100 threads of your own is a very bad idea. You're actually going to slow things down. You should be using the ThreadPool to perform some of the operations simultaneously and queue the others until a thread becomes available. You could use the ThreadPool directly or you could use the DownloadFileAsync method of the WebClient class, which inherently uses the the ThreadPool.

 

[kill4]

Actually the user wont use all the threads, I just added the 100 thing so the user could use 100 threads if he wants, but thats way over bloated, and he wont be using 100 threads more like 5 max. He specifies how many threads to use in a combo box, before he hits the start button. That being said im i still going about it the wrong way?

And is there a way to actually stop the thread from getting any more data back this way? Let me show you the timeout sub that is fired when a timeout is elapsed..

Private Sub TimedOut(ByVal Index As Integer)
        objTimeouts(Index).StopTimer() '-- Stops the timeout timer.
        '-- Resseting other varibles here, ect..
        RestartThread(Index)
    End Sub

There another sub is called were i would restart the thread that timed out. It's called RestartThread() and passes the index of the thread as a argument
Some of the code for the restartthread sub below

Private Sub RestartThread(ByVal I As Integer)
 objThreads(I) = New Thread(AddressOf objRequest(I).GetRequest)
objThreads(I).IsBackground = True
objThreads(I).Start()
End Sub

User would get sometimes a error Thread is currently running or has stopped error, on the .start method of the thread. I'm thinking he is getting this error because the thread was still doing work. I was under the impression using the "New" keyword would cause the thread to stop any previous downloading or other working and start a fresh.

So is this still the wrong way to approach this?

Hope i made my self a little more clear

Thanks for the reply..

 

[jmcilhinney]

You should be using the ThreadPool... period! Letting the user choose how many threads to run simultaneously is a diabolical idea.

 

[JohnH]

I was under the impression using the "New" keyword would cause the thread to stop any previous downloading or other working and start a fresh.

New keyword is used to create a new object, and = assignment operator is used to assign a value/object to a variable. Neither operation does directly affect any existing object.