vc++ 监控指定路径下文件变化实现代码

参考MSDN文档

https://docs.microsoft.com/zh-cn/windows/desktop/api/winbase/nf-winbase-readdirectorychangesw

https://docs.microsoft.com/zh-cn/windows/desktop/api/winnt/ns-winnt-_file_notify_information

具体看代码

# include < iostream >
 # include < windows.h >
 # include < process.h >
 # include < tchar.h >
 # include < string >
using namespace std;
typedef void( * CHANGESCALLBACK)(const std::wstring strFileName);
/*
@ 监控指定目录下文件变化
@ strDirPath 需要监控的目录
@ dwChangesType 需要监控文件变化方式
@ onCallBack 变化后的回调处理函数
 */
void CheckFilesChanges(const std::wstring strDirPath, DWORD dwChangesType, CHANGESCALLBACK onCallBack);
void PrintMsg(const std::wstring strFileName) {
  wprintf_s(L "new add File:\t %s\r\n", strFileName.c_str());
}
void CheckFilesChanges(const std::wstring strDirPath, DWORD dwChangesType, CHANGESCALLBACK onCallBack) {
  if (strDirPath.empty() || !onCallBack)
    return;
  HANDLE hDir = INVALID_HANDLE_VALUE;
  BYTE lpBuffer[1024];
  ZeroMemory(lpBuffer, 1024);
  DWORD cbBytes = NULL;
  BOOL isOk = FALSE;
  FILE_NOTIFY_INFORMATION * pnotify = (FILE_NOTIFY_INFORMATION * )lpBuffer;
  FILE_NOTIFY_INFORMATION * tmp;
  ZeroMemory( & lpBuffer, sizeof(FILE_NOTIFY_INFORMATION));
  hDir = CreateFile(strDirPath.c_str(), FILE_LIST_DIRECTORY,
      FILE_SHARE_READ |
      FILE_SHARE_WRITE |
      FILE_SHARE_DELETE, NULL,
      OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS |
      FILE_FLAG_OVERLAPPED, NULL);
  if (INVALID_HANDLE_VALUE == hDir)
    return;
  while (true) {
    isOk = ReadDirectoryChangesW(hDir, & lpBuffer,
        sizeof(lpBuffer),
        TRUE,
        FILE_NOTIFY_CHANGE_FILE_NAME | FILE_NOTIFY_CHANGE_LAST_WRITE,
         & cbBytes,
        NULL,
        NULL);
    if (isOk) {
      tmp = pnotify;
      PWSTR fileName = nullptr;
      std::wstring strFileName;
      if (tmp->FileNameLength) {
        DWORD dwLength = tmp->FileNameLength + 1;
        fileName = new wchar_t[dwLength];
        if (fileName) {
          memset(fileName, 0, dwLength * 2);
          memcpy(fileName, tmp->FileName, dwLength * 2);
          strFileName = fileName;
        }
        if (fileName)
          delete []fileName;
      }
      if (tmp->Action == dwChangesType) {
        onCallBack(strFileName);
      }
      ZeroMemory(tmp, 1024);
      /*switch (tmp->Action){
      case FILE_ACTION_ADDED: //当前目录新增文件{
      onCallBack(strFileName);
      }break;

      case FILE_ACTION_REMOVED:  //该文件已从目录中删除{
      onCallBack(strFileName);
      }
      break;
      case FILE_ACTION_MODIFIED: //该文件已被修改。也可以是时间戳或属性的更改{
      onCallBack(strFileName);
      }
      break;
      case FILE_ACTION_RENAMED_OLD_NAME: //该文件已重命名，这是旧名称。{
      onCallBack(strFileName);
      }
      break;
      case FILE_ACTION_RENAMED_NEW_NAME: //该文件已重命名，这是新名称。{
      onCallBack(strFileName);
      }
      break;
      default:
      break;
      }*/
    }
  }
  CloseHandle(hDir);
}
unsigned int CALLBACK ThreadProc(void * arg) {
  CheckFilesChanges(_T("E:\\GoCode"), FILE_ACTION_ADDED, PrintMsg);
  return 0;
}
int main(int argc, char * argv[]) {
  HANDLE hThread = NULL;
  hThread = (HANDLE)::_beginthreadex(nullptr, NULL, ThreadProc, NULL, NULL, NULL);
  system("pause");
  return 0;
}

好了这篇文章就介绍到这了，需要的朋友可以参考一下。