Converting time from UTC to Local and vice versa

Question

Hi

I am trying to figure out a way to convert a FILETIME structure from UTC to Local and vice versa.

I've been using the two functions: FileTimetoLocalFileTime() and LocalFileTimeToFileTime(). The problem seems that they do not work as expected.

As an example: First I got a local file time using:

WIN32_FIND_DATA fd;
FindFirstFile(_T("Path:To:File"), &fd);

now fd has the last write date in local format.

Then I use LocalFileTimeToFileTime() to convert the last write date to UTC and then convert that FILETIME structure to an 64bit integer as described in MSDN. http://support.microsoft.com/kb/188768 Then I store that number in a DB for later.

Now when I change the timezone for example, I get the 64bit integer from the DB. Convert it into a FILETIME structure and then try to convert it to its local value. Using FileTimeToLocalFileTime(). The problem is that when I compare that file time with the local time of the same file and of course making sure that no changes have been made to the file. The times are different. I am not sure why but its like that every time.

I Would also like to know if there is a possible way to convert the FILETIME as is to a readable string. Without using CTime or SYSTEMTIME since both of them convert the FILETIME to its UTC equivalent which I don't really want, as I would like to see the exact converted time from both functions LocalFileTimeToFileTime() and FileTimeToLocalFileTime().

Hope I've explained the situation, and hope someone would help me achieve my goal