Windows C++代碼（與CRON類似）每xx小時執行一次命令

Question

在我面臨的情況下，我需要一些C++代碼，每隔2小時執行一次命令，儘管我沒有編程C++（而不是C＃），但在這種情況下，我無法使用C＃。

有人能提供演示此請

Answer 1

C++標準庫不提供類似於C＃計時器的任何選項，您可以使用睡眠，但會掛起線程，

一個不可─一個示例代碼所以非常準確的解決方法是從初始化時鐘獲得時間，並且在一些常規執行的塊中放置一個檢查，看看時間> init +步驟，然後跳轉到你的定時器語句並重置init = cur_time ..

，或者你可以使用windows定時器：

http://www.cplusplus.com/forum/beginner/11271/ http://www.cplusplus.com/forum/windows/5531/

Answer 2

也許，簡單的東西像這樣?:

VOID WINAPI Sleep(
__in DWORD dwMilliseconds 
); 

。

while (true) 
{ 
    dosmt(); 
    sleep(2*60*60*1000); 
} 

或者在單線程中啓動它，以防其應該與剩餘的程序並行執行？這種情況boost :: thread可以提供幫助。

Answer 3

使用C++服務嚮導來創建服務，並將其插入到服務中（當然，更多錯誤陷阱）。這應該適用於大多數現代版本的Windows。

#include "stdafx.h" 
#include <windows.h> 
#include <iostream> 
using namespace std; 


/** 
A callback function. It is similar to a delegate in .Net. 
*/ 
VOID CALLBACK theTimerCallback(PVOID aParam, BOOLEAN TimerOrWaitFired) 
{ 
    // This is executed when the timer fires. 
    cout << "The timer says: Hello, world." << endl; 

    // The parameter (see below) is a handle to single the 
    // main thread to shut down. 
    HANDLE theShutdownEvent = (HANDLE)aParam; 

    // Tell the main thread to shutdown. 
    SetEvent (theShutdownEvent); 
} 



int _tmain(int argc, _TCHAR* argv[]) 
{ 

    // Assuming you have a program running some main thread, this 
    // will run a timer in the background and handle the timer callbacks. 
    // So if this is a service, this timer would execute while the main 
    // service thread can handle startup and shutdown of the service. 

    // If it is just a single thread of an application that you manually 
    // execute, then using a sleep in a loop would work fine. 


    // Creating an event to make this main thread wait. 
    HANDLE anEventHandle = CreateEvent (NULL, TRUE, FALSE, L"Shutdown event"); 


    // The queue object that handles the timers 
    HANDLE theTimerQueueHandle = CreateTimerQueue(); 


    HANDLE theTimerHandle = NULL; 

    if (CreateTimerQueueTimer (
    &theTimerHandle, // The handle to the timer is written to this variable. 
    theTimerQueueHandle, // The handle to the timer queue that tracks this timer. 
    theTimerCallback, // The callback function (see above). 
    anEventHandle, // A parameter sent to the callback function. This can be anything. 
    10000, // Time to fire, in milliseconds (10 secs). 
    0, // Execution period - 0 means it only fires once. 
    WT_EXECUTEDEFAULT // Look at the API docs and pick your own flags. 
    )) 
    { 
    cout << "Main thread waiting for timer." << endl; 
    // This makes the main thread wait until the timer fires. Normally, something like 
    // a service would have its own mechanism of waiting on the main thread. 
    WaitForSingleObject (anEventHandle, INFINITE); 


    // This shuts down all the timers, deletes their handles, waits for 
    // handler functions to finish, and deletes the timer handles as well 
    // as the queue handle. 
    DeleteTimerQueueEx (theTimerQueueHandle, INVALID_HANDLE_VALUE); 

    } 

    CloseHandle (anEventHandle); 

    cout << "Main thread exiting" << endl; 
    return 0; 
}