.NET FileInfo.LastWriteTime & FileInfo.LastAccessTime are wrong

Question

When I call FileInfo(path).LastAccessTime or FileInfo(path).LastWriteTime on a file that is in the process of being written it returns the time that the file was created, not the last time it was written to (ie. now).

Is there a way to get this information?

Edit: To all the responses so far. I hadn't tried Refresh() but that does not do it either. I am returned the time that the file was started to be written to. The same goes for the static method, and creating a new instance of FileInfo.

Codymanix might have the answer, but I'm not running Windows Server (using Windows 7), and I don't know where the setting is to test.

Edit 2: Nobody finds it interesting that this function doesn't seem to work?

Answer 1

The FileInfo values are only loaded once and then cached. To get the current value, call Refresh() before getting a property:

f.Refresh(); t = f.LastAccessTime; 

Another way to get the current value is by using the static methods on the File class:

t = File.GetLastAccessTime(path); 

Answer 2

Starting in Windows Vista, last access time is not updated by default. This is to improve file system performance. You can find details here:

http://blogs.technet.com/b/filecab/archive/2006/11/07/disabling-last-access-time-in-windows-vista-to-improve-ntfs-performance.aspx

To reenable last access time on the computer, you can run the following command:

fsutil behavior set disablelastaccess 0