VC++: How to get the time and date of a file?

问题:

How do I get the file size and date stamp of a file on Windows in C++, given its path?

回答1:

You can use FindFirstFile() to get them both at once, without having to open it (which is required by GetFileSize() and GetInformationByHandle()). It's a bit laborious, however, so a little wrapper is helpful

bool get_file_information(LPCTSTR path, WIN32_FIND_DATA* data)
{
  HANDLE h = FindFirstFile(path, &data);
  if(INVALID_HANDLE_VALUE != h) {
    return false;
  } else {
    FindClose(h);
    return true;
  }
}

Then the file size is available in the nFileSizeHigh and nFileSizeLow members of WIN32_FIND_DATA, and the timestamps are available in the ftCreationTime, ftLastAccessTime and ftLastWriteTime members.

回答2:

You could also use POSIX stat, if you were looking for portability. Windows still supports its use.

回答3:

GetFileSize/GetFileSizeEx and GetFileInformationByHandleEx with FileBasicInfo can be used to retrieved this information.

Both functions take a handle, so you need to use CreateFile on the path prior to calling these functions.

// Error handling removed for brevity
HANDLE hFile = CreateFile(path, GENERIC_READ, FILE_SHARE_READ,
                 NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);

LARGE_INTEGER fileSize;
GetFileSizeEx(hFile, &fileSize);

FILE_BASIC_INFO fileInfo);
GetFileInformationByHandle(hFile, FileBasicInfo, fileInfo, sizeof(fileInfo));

// fileInfo.CreationTime is when file was created.

回答4:

To append the other answer, you call GetFileTime to get just the file times. This API also requries a handle and I think is easier than GetFileInformationByHandle API. BTW the GetFileInformationByHandleEx is only supported in VISTA and above.