private bool Cancel(bool abortExecution)
{
#if (_WINDOWS_CE)
if(abortExecution)
{
throw new ArgumentOutOfRangeException("abortExecution", "WindowsCE doesn't support this feature");
}
#endif
bool success = false;
bool signalComplete = false;
lock (this)
{
switch (GetWorkItemState())
{
case WorkItemState.Canceled:
//Debug.WriteLine("Work item already canceled");
if (abortExecution)
{
Thread executionThread = Interlocked.CompareExchange(ref _executingThread, null, _executingThread);
if (null != executionThread)
{
executionThread.Abort(); // "Cancel"
// No need to signalComplete, because we already cancelled this work item
// so it already signaled its completion.
//signalComplete = true;
}
}
success = true;
break;
case WorkItemState.Completed:
//Debug.WriteLine("Work item cannot be canceled");
break;
case WorkItemState.InProgress:
if (abortExecution)
{
Thread executionThread = Interlocked.CompareExchange(ref _executingThread, null, _executingThread);
if (null != executionThread)
{
executionThread.Abort(); // "Cancel"
success = true;
signalComplete = true;
}
}
else
{
success = true;
signalComplete = true;
}
break;
case WorkItemState.InQueue:
// Signal to the wait for completion that the work
// item has been completed (canceled). There is no
// reason to wait for it to get out of the queue
signalComplete = true;
//Debug.WriteLine("Work item canceled");
success = true;
break;
}
if (signalComplete)
{
SignalComplete(true);
}
}
return success;
}