• 隐式使用工作项

#include 
     
      #include 
      
       int g_nCount = 0;VOID NTAPI SimpleCallback(PTP_CALLBACK_INSTANCE pInstance, PVOID pvContext){    g_nCount++;    printf("test:%d\n", g_nCount);}void main(){    int nCount = 500;    PTP_SIMPLE_CALLBACK pFunc = SimpleCallback;    while (0 != nCount)    {        TrySubmitThreadpoolCallback(pFunc, NULL, NULL);        nCount--;    }    getchar();}
      
     

 

通过结果观察发现，利用了线程池，输出并非有序：

 

显式地控制工作项

void main(){    g_pWorkItem = CreateThreadpoolWork(TaskHandler, NULL, NULL);    if (NULL == g_pWorkItem)    {        return;    }    int nCount = 5000;    while (nCount)    {        SubmitThreadpoolWork(g_pWorkItem);        nCount--;    }    WaitForThreadpoolWorkCallbacks(g_pWorkItem, FALSE);    CloseThreadpoolWork(g_pWorkItem);    getchar();}

如果改为下面这样，则会报错：

int g_nCount = 0;PTP_WORK g_pWorkItem = NULL;void NTAPI TaskHandler(PTP_CALLBACK_INSTANCE Instance, PVOID Context, PTP_WORK work){    g_nCount++;    printf("test:%d..\n", g_nCount);}unsigned int _stdcall testthread(PVOID pParam){    int nCount = 500;    while (nCount)    {        SubmitThreadpoolWork(g_pWorkItem);        nCount--;    }    return 0;}void main(){    g_pWorkItem = CreateThreadpoolWork(TaskHandler, NULL, NULL);    if (NULL == g_pWorkItem)    {        return;    } 　　_beginthreadex(NULL, 0, testthread, NULL, 0, NULL);    WaitForThreadpoolWorkCallbacks(g_pWorkItem, FALSE);    CloseThreadpoolWork(g_pWorkItem);    getchar();}

因为据书上说，只能取消或等待本线程中的工作项。