Problem canceling background worker operation.

Hi VBForums,

I am invoking delegates in a backgroundworker so they don't block the UI. I pass in a delegate using AddressOf to a method called StartJob, which invokes the delegate in the backgroundworker. This works fine, but if the method that gets invoked in the DoWork event is a long running, UI Blocking operation (which it is) I can't seem to figure out how to cancel it if need be. Here are the example classes and form required to understand what I'm talking about!

Example class 1:

Imports System.ComponentModel

Public Class Job

Public WithEvents _bw As BackgroundWorker

Public Delegate Sub StartDel()
Public _del As StartDel

Public Event JobComplete()
Public Event ProgressUpdated()

Public Property Name
Public Property Type
Public Property Progress
Public Property Cancelled

Public Sub StartJob(ByVal del As StartDel)
_del = del
_bw = New BackgroundWorker
_bw.WorkerSupportsCancellation = True
_bw.WorkerReportsProgress = True
_bw.RunWorkerAsync()
End Sub

Public Sub StopJob()
Me.Cancelled = True
End Sub

Private Sub bw_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles _bw.DoWork
If Me.Cancelled = True Then
e.Cancel
Else
_del.Invoke()
End If
End Sub

End Class

Example Class 2

Public Class Test

Sub Start()
Work()
End Sub

Sub Work()
For i = 0 To 10
System.Threading.Thread.Sleep(2000)
MsgBox("Work done")
Next
End Sub

End Class

Example Form 1

Public Class TestForm

Private t As New Test
Private j As New Job

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
j.StartJob(AddressOf t.Start)
End Sub

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
j.StopJob()
End Sub

End Class

Calling j.StopJob doesn't stop the loop that gets invoked in the BG Worker...why? :ehh:

EDIT: Realized I had a property in the Job class called Job...was unnecessary so I removed it, woops. Still need an answer though!