C/C++ 學習之 定時器，學習定時器

C/C++ 學習之 定時器，學習定時器

下面是兩個簡單的例子，說明在  windows  控制台應用程式中定時器的用法

1、直接聲明回呼函數，然後在回呼函數中處理訊息。

// programe for timer#include "stdio.h"#include "conio.h"#include <Windows.h>int count = 0;void CALLBACK TimerProc (HWND hwnd, UINT message, UINT iTimerID, DWORD dwTime){printf("WM_TIMER in work thread count = %d\n",count++);}int main(){SetTimer (NULL, 0, 1000, TimerProc);MSG msg;    while(GetMessage(&msg,NULL,0,0))    {if(msg.message==WM_TIMER){DispatchMessage(&msg);if(count == 7){printf("should stop!\n");break;}}    }KillTimer (NULL, 0);return 0;}

2、建立線程，線上程中建立訊息處理機制

//programe for timer

#include   <windows.h>  #include   <stdio.h>  #include   <conio.h>  unsigned   long   WINAPI   Thread(PVOID   pvoid); void   main()  {      DWORD   dwThreadId;      printf("控制台應用程式：線程-定時器\n");      HANDLE hThread = CreateThread(NULL, 0, Thread, 0, 0, &dwThreadId);//安全等級，預設棧空間，線程名，線程參數，編程標誌，線程ID                       DWORD   dwwait = WaitForSingleObject(hThread,1000*30);      switch(dwwait)    {      case   WAIT_ABANDONED:          printf("main thread WaitForSingleObject return WAIT_ABANDONED\n");          break;      case   WAIT_OBJECT_0:          printf("main thread WaitForSingleObject return WAIT_OBJECT_0\n");          break;      case   WAIT_TIMEOUT:          printf("main thread WaitForSingleObject return WAIT_TIMEOUT\n");          break;      }      CloseHandle(hThread);      getch();  }  unsigned  long   WINAPI   Thread(PVOID   pvoid)  {      MSG   msg;    PeekMessage(&msg,   NULL,   WM_USER,   WM_USER,   PM_NOREMOVE);//該函數為一個訊息檢查線程訊息佇列，並將該訊息（如果存在）放於指定的結構。//接收訊息的 MSG 結構指標，控制代碼，指定被檢查的訊息範圍裡的第一個訊息，最後一個，確定訊息如何被處理//PM_NOREMOVE，PeekMessage處理後，訊息不從隊列裡除掉//PM_REMOVE，PeekMessage處理後，訊息從隊列裡除掉//PM_NOYIELD，此標誌使系統不釋放等待調用程式閒置線程    UINT   timerid = SetTimer(NULL,111,1000,NULL);      BOOL   bRet;      int   count = 0;      while((bRet = GetMessage(&msg, NULL, 0, 0)) != 0)      {            if(bRet == -1)          {              //   handle   the   error   and   possibly   exit          }          else if(msg.message == WM_TIMER)         {              printf("WM_TIMER in work thread count = %d\n",count++);              if(count>4)  break;          }          else          {              TranslateMessage(&msg);   //將虛擬鍵訊息轉換為字元訊息,下一次線程調用函數GetMessage或PeekMessage時被讀出。            DispatchMessage(&msg);   //該函數分發一個訊息給視窗程序,訊息傳遞給作業系統，然後作業系統去調用我們的回呼函數        }      }      KillTimer(NULL,timerid);      printf("thread  end  here\n");      return   0;  }