Choose the newest file from each directory

Question

I am using this to choose a root folder and take the newest file from each directory before adding this files into my listbox but in some cases it does not choose the newest file.

var rootDirFile = Directory
    .EnumerateFiles(pathToSearch, "*.doc", SearchOption.TopDirectoryOnly)
    .OrderByDescending(f => File.GetLastWriteTime(f))
    .Take(1);

var allNewestFilesOfEachFolder = Directory
    .EnumerateDirectories(pathToSearch, "*.*", SearchOption.AllDirectories)
    .Select(d => Directory.EnumerateFiles(d, "*.doc")
        .OrderByDescending(f => File.GetLastWriteTime(f))
        .FirstOrDefault());

foreach (string tempFile in rootDirFile.Concat(allNewestFilesOfEachFolder))
{
    //add the file
}

Maybe you can use GetCreationTime instead of GetLastWriteTime — M. Mennan Kara, Jan 29 '13 at 10:59
According to this : http://stackoverflow.com/questions/3360324/checking-when-a-file-was-last-modified-in-c-sharp-on-windows-os that is the way to go. — radu florescu, Jan 29 '13 at 10:59
Are you looking for the last created file or the last modified one? — Sandeep, Jan 29 '13 at 11:02
last created file but i can see that GetCreationTime() solve my problem, is it the best way to do it ? — user1269592, Jan 29 '13 at 11:12

score 1 · Answer 1 · edited May 23 '17 at 11:56

1

File.GetLastWriteTime Is not always reliable on WindowsVista/7 (see my answer in this post) as it could seem.

To create more reliable solution, you may use think about FileSystemWatcher, but in that case you would need to use some kind of running service.

Or can think about use if File.GetCreationTime, if that "new" files are actually created every time.

edited May 23 '17 at 11:56

Community

1
1

answered Jan 29 '13 at 10:59

Tigran

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score 0 · Answer 2 · answered Jan 29 '13 at 11:02

We've been using this for a while and don't seem to have any problems.

We can't use File.GetCreationTime since edits are made in files regardless of creation time.

while (Directory.GetFiles(dir, "*", SearchOption.TopDirectoryOnly).Count() > 7)
  {
     DirectoryInfo dirInfo = new DirectoryInfo(dir);
     FileSystemInfo fileInfo = dirInfo.GetFileSystemInfos().OrderBy(fileT => fileT.LastWriteTime).First();
     File.Delete(fileInfo.FullName);
  }

score 0 · Answer 3 · answered Jan 29 '13 at 11:22

This should give you a list of directory/latest file pairs:

var latestByDirectory = new DirectoryInfo(_strPath)
    .GetDirectories()
    .Select(d => new
    {
         Directory = d,
        LatestFile = d.GetFiles()
            .OrderByDescending(f => f.CreationTime)
            .DefaultIfEmpty((FileInfo)null)
            .ToList().First()
    });

Choose the newest file from each directory

3 Answers3