Question

我有这个代码，它抓取某个目录中的文件。我想按时过滤这些文件。我希望文件类型过滤20秒或更短。如何将此过滤器添加到我的代码中？谢谢。

using namespace std; 
typedef vector<WIN32_FIND_DATA> tFoundFilesVector; 
std::wstring LastWriteTime;   
int getFileList(const char * filespec, tFoundFilesVector &foundFiles)
{ 
    WIN32_FIND_DATA findData; 
    HANDLE h; 
    int validResult=true; 

    int numFoundFiles = 0; 
    h = FindFirstFile((LPCSTR)filespec, &findData); //ansi 
    if (h == INVALID_HANDLE_VALUE) 
    return 0; 

    while (validResult) 
    { 
    numFoundFiles++; 
    foundFiles.push_back(findData); 
    validResult = FindNextFile(h, &findData); 
    } 
    return numFoundFiles; 
} 

void showFileAge(tFoundFilesVector &fileList) 
{ 
    unsigned _int64 fileTime, curTime, age; 
    tFoundFilesVector::iterator iter; 
    FILETIME ftNow; 
    CoFileTimeNow(&ftNow); 
    curTime = ((_int64) ftNow.dwHighDateTime << 32) + ftNow.dwLowDateTime; 

    for (iter=fileList.begin(); iter<fileList.end(); iter++) 
    { 
        fileTime = ((_int64)iter->ftLastWriteTime.dwHighDateTime << 32) + iter->ftLastWriteTime.dwLowDateTime; 

        age = curTime - fileTime; 

        wcout << "FILE: '" << iter->cFileName << "', AGE: " << (_int64)age/10000000UL << "  seconds" << endl; 
    } 
} 

int main() 
{ 
   string fileSpec = "*.*"; 
   tFoundFilesVector foundFiles; 
   tFoundFilesVector::iterator iter; 

   int foundCount = 0; 

   getFileList("c:\\Mapper\\*.txt", foundFiles); 
   getFileList("c:\\Mapper\\*.jpg", foundFiles);
     foundCount = foundFiles.size(); 
    if (foundCount) 
    { 
        wcout << "Found "<<foundCount<<" matching files.\n"; 
        showFileAge(foundFiles); 
    } 
    system("pause"); 
    return 0; 
}

Answer 1

你去吧。我更改了FindFile调用以显式使用“A”版本（并明确使用WIN32_FIND_DATAA而不是WIN32_FIND_DATA）。对LPCSTR的投射看起来很可疑，但我不知道你是否正在使用unicode进行编译（默认情况下Visual Studio默认为Unicde“W”apis）。

另外，你没有调用FindClose，我补充说。否则，我只使用GetSystemTime获取当前时间，将其转换为文件时间，然后将文件时间引用为64位整数。 “unsigned long long”与unsigned __int64相同。

using namespace std; 
typedef vector<WIN32_FIND_DATAA> tFoundFilesVector; 
std::wstring LastWriteTime; 

unsigned long long FileTimeToULL(const FILETIME& ft)
{
    unsigned long long ull;
    ull = ft.dwLowDateTime | (((unsigned long long)ft.dwHighDateTime) << 32);
    return ull;
}

int getFileList(const char * filespec, tFoundFilesVector &foundFiles, DWORD dwMaxAgeInSeconds)
{ 
    WIN32_FIND_DATAA findData={}; 
    HANDLE h; 
    int validResult=true; 
    int numFoundFiles = 0; 
    unsigned long long now = 0;
    unsigned long long age = 0;

    SYSTEMTIME stnow = {};
    FILETIME ftnow = {};
    ::GetSystemTime(&stnow);
    ::SystemTimeToFileTime(&stnow, &ftnow);
    now = FileTimeToULL(ftnow);

    h = FindFirstFileA(filespec, &findData); //ansi 
    validResult = (h != INVALID_HANDLE_VALUE);

    while (validResult) 
    { 
        bool fIsDirectory = !!(findData.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY);
        age = FileTimeToULL(findData.ftLastWriteTime);
        if (age > now)
        {
            age = 0;
        }
        else
        {
            age = now - age;
        }

        // age is the diff between "right now" and when the file was last touched (in 100ns units)

        // convert to seconds
        age /= 10000000;

        if ((age <= dwMaxAgeInSeconds) && (!fIsDirectory))
        {
            foundFiles.push_back(findData); 
            numFoundFiles++; 
        }

        validResult = FindNextFileA(h, &findData); 
    } 

    if (h != INVALID_HANDLE_VALUE)
    {
        FindClose(h);
    }

    return numFoundFiles; 
}

添加过滤器

1 个答案: