multi-thread

win32 方式

c++ 方式

CPP RunTime Library

_beginthreadex, _endthreadex
_endthreadex need calling the Win32 CloseHandle API

注意：在使用了MFC的程序中不能够使用该函数创建线程，而应该使用MFC提供的线程函数
MFC relies on some thread - local variables and state.AfxBeginThread
initializes those, then calls _beginthreadex for you.Just part of the
preconditions for using the library.If you don’t use AfxBeginThread some
of your calls to MFC functions could encounter uninitialized pointers.

//_beginthread use
#include <process.h>

//friend function can access private member
friend unsigned int __stdcall threadReadProc(void* pArguments);

//monitor thread use
HANDLE        hThread;

void startListener()
{
    // Create the second thread.
    m_hThreadPay = (HANDLE)_beginthreadex(NULL, 0, &threadReadProc, this, 0, NULL);
    if (NULL == m_hThread)
    {
        return RET_FAILED;
    }
    // Wait until second thread terminates. If you comment out the line
    // below, Counter will not be correct because the thread has not
    // terminated, and Counter most likely has not been incremented to
    // 1000000 yet.
    WaitForSingleObject(m_hThreadPay, INFINITE);
    printf("Counter should be 1000000; it is-> %d\n", Counter);
    // Destroy the thread object.
    CloseHandle(m_hThreadPay);
    _endthreadex(0);

}

unsigned int __stdcall threadReadProc(void* pArguments)
{
  CMainDlg* pwnd = (CMainDlg*)pArguments;
    ::WaitForSingleObject(hEvent, INFINITE);
    ...
        CloseHandle(hThread);
    g_hThreadProc = NULL;
    _endthreadex(0);//ensure proper recovery of resources allocated for the thread.
    return 0;
}

暂停线程

对于暂停线程可以使用信号量来控制

//seconde param TRUE manual reset, FALSE auto-reset, third param initial state
HANDLE hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

在需要暂停的地方用
::WaitForSingleObject(hEvent, -1);

// 最多等待 10 s
WaitForMultipleObjects(m_curInfo.vEvtThread.size(), &m_curInfo.vEvtThread[0], TRUE, 10000);

::SetEvent(hEvent);//go on
::ResetEvent(hEvent);//pause

MFC 方式

// 启动时，设置优先级
AfxBeginThread(threadWorkerFrontend, this, THREAD_PRIORITY_TIME_CRITICAL);

CWinThread* m_pThread = AfxBeginThread(threadReadProc, this);
UINT threadReadProc(LPVOID lpParam)
{
    while (iAbort == 0)
    {

    }
    return 0;
}

iAbort = 1;
::WaitForSingleObject(m_pThread->m_hThread, INFINITE);

m_pThread->SuspendThread();
m_pThread->ResumeThread();

AfxEndThread(0);
TerminateThread(m_pThread, 0);

参考代码，这里的 CWinThread 会在线程结束后自动释放。

工作线程

CWinThread* m_pThread = AfxBeginThread(threadReadProc, this);
UINT threadReadProc(LPVOID lpParam)
{
    while (iAbort == 0)
    {

    }
    return 0;
}

iAbort = 1;
::WaitForSingleObject(m_pThread->m_hThread, INFINITE);

m_pThread->SuspendThread();
m_pThread->ResumeThread();

AfxEndThread(0);
TerminateThread(m_pThread, 0);

更新UI界面

使用自定义消息

// 更新统计界面数据
#define WM_UIMESSAGE (WM_USER + 201)

BEGIN_MESSAGE_MAP(CDlgQueryPeople, CDialogEx)
    ...
	ON_MESSAGE(WM_UIMESSAGE, &CnngDemoServerDlg::OnUIMessage)
END_MESSAGE_MAP()

LRESULT CDlgQueryPeople::OnUIMessage(WPARAM wParam, LPARAM lParam)
{
	if (wParam != 0) {
		int cnt = m_list_statistic.GetItemCount();
		m_list_statistic.InsertItem(cnt, *((CString*)wParam));
	}

	return 0;
}

afx_msg LRESULT OnUIMessage(WPARAM wParam, LPARAM lParam);