[VUEDUE]

I've been learning more and more about threading and multi-threading in VB. I wrote this code below:

Code

Dim max As Integer = NumericalUpDown1.Value - 1
            For X As Integer = 0 To max
                System.Threading.ThreadPool.QueueUserWorkItem(Sub() myTHREAD())
            Next

However, lets say the threads do something infinite; a loop maybe. How do I kill all threads in the threadpool?

I've searched around but I didn't manage to find a clean solution.

[HFDone]

its not up to threadpool choose when to stop it in your loop

[VUEDUE]

its not up to threadpool choose when to stop it in your loop

Well I realized I could set a parameter. I could do something like:

Code

Public var As Integer = 0

'Change var to equal '1' somewhere along the line.


Public Sub myThread()
Do
     If var == 1 Then
          Exit Do
     End If

     Console.WriteLine("Loop is still going!")
Loop

Console.WriteLine("Done!")
End Sub

Just as a quick example yenno. But I figured there would be a systematic way to do it.

[Shadow_Cloud]

Is there any specific reason you aren't using a cancellationToken?
https://docs.microsoft.com/en-us/dotnet/...ew=net-5.0

Your example won't allow thread safe access to the variable you are checking.

[VUEDUE]

Is there any specific reason you aren't using a cancellationToken?
https://docs.microsoft.com/en-us/dotnet/...ew=net-5.0

I had no idea they existed up until now, but I'll look into it.

Your example won't allow thread safe access to the variable you are checking.

How so? I'm not sure what you mean by that.

[Shadow_Cloud]

I had no idea they existed up until now, but I'll look into it.


How so? I'm not sure what you mean by that.

So imagine you had 10 threads and 2 of them need to stop. Based on your implementation below, you wouldn't be able to tell which ones need to stop and which ones need to carry on. This will actually just kill all of them.

Code

Public var As Integer = 0

'Change var to equal '1' somewhere along the line.


Public Sub myThread()
Do
     If var == 1 Then
          Exit Do
     End If

     Console.WriteLine("Loop is still going!")
Loop

You could have something like a concurrentDictionary keep track of the threads and their running state so you only need to have the thread do a lookup on its own ID to determine if it should be cancelled.