How to retrieve list of files in directory, sorted

问题:

I am trying to get a list of all files in a folder from C#. Easy enough:

Directory.GetFiles(folder)

But I need the result sorted alphabetically-reversed, as they are all numbers and I need to know the highest number in the directory. Of course I could grab them into an array/list object and then do a sort, but I was wondering if there is some filter/parameter instead?

They are all named with leading zeros. Like:

00000000001.log
00000000002.log
00000000003.log
00000000004.log
..
00000463245.log
00000853221.log
00024323767.log

Whats the easiest way? I dont need to get the other files, just the "biggest/latest" number.

回答1:

var files = Directory.EnumerateFiles(folder)
                     .OrderByDescending(filename => filename);

(The EnumerateFiles method is new in .NET 4, you can still use GetFiles if you're using an earlier version)

---

EDIT: actually you don't need to sort the file names, if you use the MaxBy method defined in MoreLinq:

var lastFile = Directory.EnumerateFiles(folder).MaxBy(filename => filename);

回答2:

var files = from file in Directory.GetFiles(folder)    
               orderby file descending 
               select file;

var biggest = files.First();

---

if you are really after the highest number and those logfiles are named like you suggested, how about:

Directory.GetFiles(folder).Length

回答3:

Extending what @Thomas said, if you only need the top X files, you can do this:

int x = 10;
var files = Directory.EnumerateFiles(folder)
                 .OrderByDescending(filename => filename)
                 .Take(x);