在线请教：我用findfirstchangenotification监视文件夹是否不改变，但我如何知道是该文件夹下哪一个文件的改变谢谢

Question

在线请教：我用findfirstchangenotification监视文件夹是否不改变，但我如何知道是该文件夹下哪一个文件的改变谢谢

Answer 1

// FileWatch.cpp: implementation of the CFileWatch class.
//
//////////////////////////////////////////////////////////////////////#include "stdafx.h"
#include "WatchFile.h"
#include "FileWatch.h"#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////CFileWatch::CFileWatch()
{
hCompPort=NULL; 
m_bStop = true;
numDirs = 0;
memset(DirInfo,0,sizeof(DIRECTORY_INFO)*MAX_DIRS);
}CFileWatch::~CFileWatch()
{}
BOOL CFileWatch::WatchDirectories( char *lpStrpath )
{
if(numDirs > MAX_DIRS)
return false;
DirInfo[numDirs].hDir = CreateFile( lpStrpath,
FILE_LIST_DIRECTORY,
FILE_SHARE_READ |
FILE_SHARE_WRITE |
FILE_SHARE_DELETE,
NULL,
OPEN_EXISTING,
FILE_FLAG_BACKUP_SEMANTICS |
FILE_FLAG_OVERLAPPED,
NULL);

if( DirInfo[numDirs].hDir == INVALID_HANDLE_VALUE )
{
return false;
}
    strcpy( DirInfo[numDirs].lpszDirName, lpStrpath );
hCompPort=CreateIoCompletionPort( DirInfo[numDirs].hDir,
hCompPort,(DWORD) &DirInfo[numDirs],0);
numDirs ++;
if(m_bStop)
{
    AfxBeginThread(Watch,this);
m_bStop = !m_bStop;
}
return true;
}
void CFileWatch::WatchDirectories( HANDLE hCompPort )
{
    DWORD   i;
//    DWORD   tid;
//    HANDLE  hThread;
    // Start watching each of the directories of interest    for (i=0;i<numDirs;i++)
    {
        if(!ReadDirectoryChangesW( DirInfo[i].hDir,
                               DirInfo[i].lpBuffer,
                               MAX_BUFFER,
                               TRUE,
                               FILE_NOTIFY_CHANGE_LAST_WRITE,
                               &DirInfo[i].dwBufLength,
   &DirInfo[i].Overlapped,
                               NULL))
{
int tt=GetLastError();
}
    }    // Create a thread to sit on the directory changes CWinThread *pThread =  AfxBeginThread(HandleDirectoryChange,(LPVOID)hCompPort);
//    hThread = CreateThread( NULL,
//                            0,
//                            (LPTHREAD_START_ROUTINE) HandleDirectoryChange,(LPVOID)
//                            hCompPort,
//                            0,
//                            &tid);
    WaitForSingleObject( pThread->m_hThread, INFINITE );
    CloseHandle( pThread->m_hThread );
}
void CFileWatch::CheckChangedFile( LPDIRECTORY_INFO lpdi,
                              PFILE_NOTIFY_INFORMATION lpfni)
{
TRACE("test is ok\n");
/*
    TCHAR      szFullPathName[MAX_PATH];
    TCHAR      *p;
    HANDLE     hFile;
    FILETIME   LocalFileTime;
    SYSTEMTIME SystemTime;
    BY_HANDLE_FILE_INFORMATION FileInfo;    p = FileList;    while(*p && lstrcmpi(p,lpfni->FileName))
        p+=(lstrlen(p)+1);    if(*p)
    {
        lstrcpy( szFullPathName, lpdi->lpszDirName );
        lstrcat( szFullPathName, L"\\" );
        lstrcat( szFullPathName, lpfni->FileName );        // we assume that the file was changed, since 
        // that is the only thing we look for in this sample
        wprintf( L"%s changed,", szFullPathName );        hFile=CreateFile( szFullPathName,
                          GENERIC_READ,
                          FILE_SHARE_READ,
                          NULL,
                          OPEN_EXISTING,
                          FILE_FLAG_SEQUENTIAL_SCAN,
                          0);        GetFileInformationByHandle( hFile, &FileInfo );        FileTimeToLocalFileTime( &(FileInfo.ftLastWriteTime), &LocalFileTime );        FileTimeToSystemTime( &LocalFileTime, &SystemTime );        wprintf( L" Size = %d bytes,", FileInfo.nFileSizeLow );
        wprintf( L" Last Access = %02d/%02d/%02d %02d:%02d:%02d",
                 SystemTime.wMonth,
                 SystemTime.wDay,
                 SystemTime.wYear,
                 SystemTime.wHour,
                 SystemTime.wMinute,
                 SystemTime.wSecond );        CloseHandle( hFile );        wprintf( L"\n" );
    }
*/
}
UINT CFileWatch::HandleDirectoryChange( LPVOID pParam )
{
HANDLE dwCompletionPort =  (HANDLE) pParam;
if(dwCompletionPort == NULL)
return 0;
    DWORD numBytes;
    DWORD cbOffset;
    LPDIRECTORY_INFO di;
    LPOVERLAPPED lpOverlapped;
    PFILE_NOTIFY_INFORMATION fni;    do
    {
        // Retrieve the directory info for this directory
        // through the completion key
        GetQueuedCompletionStatus( (HANDLE) dwCompletionPort,
                                   &numBytes,
                                   (LPDWORD) &di,
                                   &lpOverlapped,
                                   INFINITE);
int tt =0;        if ( di )
        {            fni = (PFILE_NOTIFY_INFORMATION)di->lpBuffer;            do
            {
                cbOffset = fni->NextEntryOffset;                if( fni->Action == FILE_ACTION_MODIFIED )
{
                    CheckChangedFile( di, fni );
}                fni = (PFILE_NOTIFY_INFORMATION)((LPBYTE) fni + cbOffset);            } while( cbOffset );            // Reissue the watch command
            ReadDirectoryChangesW( di->hDir,di->lpBuffer,
                                   MAX_BUFFER,
                                   TRUE,
                                   FILE_NOTIFY_CHANGE_LAST_WRITE,
                                   &di->dwBufLength,
                                   &di->Overlapped,
                                   NULL);
        }    } while( di ); return 0;
}void CFileWatch::Reset()
{}void CFileWatch::StopWatch()
{
    PostQueuedCompletionStatus( hCompPort, 0, 0, NULL );
Reset();
}UINT CFileWatch::Watch(LPVOID pParam)
{
CFileWatch *watch =(CFileWatch*)pParam;
if(watch == NULL)
return 1;
watch->WatchDirectories(watch->hCompPort);
return 0;}

Answer 2

或者使用SHChangeNotifyRegister/SHChangeNotifyDeregister.LRESULT CThumbnailListCtrl::OnFileChanged(WPARAM wParam, LPARAM lParam)
{
SHNotifyInfo* pShellInfo = (SHNotifyInfo*)wParam;

if(m_strCurrentDir.IsEmpty())
{
return 0;
} switch(lParam)
{
    case SHCNE_DELETE:
{
//deleted file
CString strPathName = GetPathFromPIDL(pShellInfo->dwItem1);
CString strPath = ExtractPath(strPathName); break;
}............
}