How to find the most recent file in a directory using .NET, and without looping?

Question

how about something like this...

var directory = new DirectoryInfo("C:\\MyDirectory");
var myFile = (from f in directory.GetFiles()
             orderby f.LastWriteTime descending
             select f).First();

// or...
var myFile = directory.GetFiles()
             .OrderByDescending(f => f.LastWriteTime)
             .First();

Expanding on the first one above, if you want to search for a certain pattern you may use the following code:

string pattern = "*.txt";
var dirInfo = new DirectoryInfo(directory);
var file = (from f in dirInfo.GetFiles(pattern) orderby f.LastWriteTime descending select f).First();

If you want to search recursively, you can use this beautiful piece of code:

public static FileInfo GetNewestFile(DirectoryInfo directory) {
   return directory.GetFiles()
       .Union(directory.GetDirectories().Select(d => GetNewestFile(d)))
       .OrderByDescending(f => (f == null ? DateTime.MinValue : f.LastWriteTime))
       .FirstOrDefault();                        
}

Just call it the following way:

FileInfo newestFile = GetNewestFile(new DirectoryInfo(@"C:\directory\"));

and that's it. Returns a FileInfo instance or null if the directory is empty.

A non-LINQ version:

/// <summary>
/// Returns latest writen file from the specified directory.
/// If the directory does not exist or doesn't contain any file, DateTime.MinValue is returned.
/// </summary>
/// <param name="directoryInfo">Path of the directory that needs to be scanned</param>
/// <returns></returns>
private static DateTime GetLatestWriteTimeFromFileInDirectory(DirectoryInfo directoryInfo)
{
    if (directoryInfo == null || !directoryInfo.Exists)
        return DateTime.MinValue;

    FileInfo[] files = directoryInfo.GetFiles();
    DateTime lastWrite = DateTime.MinValue;

    foreach (FileInfo file in files)
    {
        if (file.LastWriteTime > lastWrite)
        {
            lastWrite = file.LastWriteTime;
        }
    }

    return lastWrite;
}

/// <summary>
/// Returns file's latest writen timestamp from the specified directory.
/// If the directory does not exist or doesn't contain any file, null is returned.
/// </summary>
/// <param name="directoryInfo">Path of the directory that needs to be scanned</param>
/// <returns></returns>
private static FileInfo GetLatestWritenFileFileInDirectory(DirectoryInfo directoryInfo)
{
    if (directoryInfo == null || !directoryInfo.Exists)
        return null;

    FileInfo[] files = directoryInfo.GetFiles();
    DateTime lastWrite = DateTime.MinValue;
    FileInfo lastWritenFile = null;

    foreach (FileInfo file in files)
    {
        if (file.LastWriteTime > lastWrite)
        {
            lastWrite = file.LastWriteTime;
            lastWritenFile = file;
        }
    }
    return lastWritenFile;
}

Short and simple:

new DirectoryInfo(path).GetFiles().OrderByDescending(o => o.LastWriteTime).FirstOrDefault();

Another approach if you are using Directory.EnumerateFiles and want to read files in latest modified by first.

foreach (string file in Directory.EnumerateFiles(fileDirectory, fileType).OrderByDescending(f => new FileInfo(f).LastWriteTime))

}