I would amend your code something like this.
Have some member variables in your dialog class to hold the thread handle and an event handle (initialise to NULL in the constructor):
CWinThread* m_hThread;
HANDLE m_hKillEvent;
Use a static function as your thread entry point, pass the dialog this
as the parameter, then delegate the call back to the class instance so you have access to all of the dialog's variables:
UINT ThreadFunc(LPVOID pParam)
{
// static thread func - delegate to instance
CprogCtrlDlg* pDlg = static_cast<CprogCtrlDlg*>(pParam);
return pDlg->ThreadFuncRun();
}
When you start the thread, create an event too:
void CprogCtrlDlg::OnBnClickedStart()
{
// create worker thread
m_hKillEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
m_hThread = AfxBeginThread(ThreadFunc, this);
AfxMessageBox(L"Thread started");
}
To kill the thread, just set the event and wait on the thread handle, which will get signaled on death:
void CprogCtrlDlg::OnBnClickedCancel()
{
// kill the Worker thread
SetEvent(m_hKillEvent);
// wait for it to die
DWORD dwRet = WaitForSingleObject(m_hThread->m_hThread, 5000);
if (dwRet == WAIT_TIMEOUT)
{
// thread failed to die after 5 seconds
// error handling (maybe TerminateThread here)
}
}
In the thread function (now in the dialog class) you can post messages to yourself to indicate progress and use a wait on the event to catch a kill request:
UINT CprogCtrlDlg::ThreadFuncRun()
{
// instance thread func
PostMessage(WM_UPDATE_CONTROL, 0, 0);
// main loop
while (true)
{
// check kill
DWORD dwRet = WaitForSingleObject(m_hKillEvent, 0);
if (dwRet == WAIT_OBJECT_0) break;
// do a little work here and update progress
// ... so this is part of your working loop ...
PostMessage(WM_UPDATE_CONTROL, 0, 1 /*2,3,4,...*/);
}
// normal thread exit
PostMessage(WM_STOP_CONTROL, 0, 0);
return 0;
}
I've left out initialisation, cleanup of pointers, handles etc. but you get the general idea I hope.
There are several ways you can code the thread loop, you can do it like above where you periodically check to see if the event is signaled, or you can wait on the event to get signaled to do the work. Both are common patterns and often used together with two events - one for triggering work and the other for killing. See this answer for some important points to note if waiting on multiple events.
For a simple progress bar update, you can put the event check inside the work loop, something like this:
UINT CprogCtrlDlg::ThreadFuncRun()
{
// instance thread func
PostMessage(WM_UPDATE_CONTROL, 0, 0);
// main loop
for (int i = 0; i < 100; ++i)
{
// check kill
DWORD dwRet = WaitForSingleObject(m_hKillEvent, 0);
if (dwRet == WAIT_OBJECT_0) break;
// do a little work here and update progress
PostMessage(WM_UPDATE_CONTROL, 0, (LPARAM)i);
}
// normal thread exit
PostMessage(WM_STOP_CONTROL, 0, 0);
return 0;
}