How to custom sort the return values of Directory.GetFiles()

Question

I am loading a list of files placed in a directory in a string array. I am using System.IO.Directory.GetFiles(),

String[] path = Directory.GetFiles(batchElements[j].DocIdPath, "*.csv", SearchOption.AllDirectories);

I'm assuming the default sort order of the returned values is by name. So my files are loaded in the following order.

• 2713_CFPB Settlement Cost Booklet_2713_1.csv
• 2713_CFPB Settlement Cost Booklet_2713_10.csv
• 2713_CFPB Settlement Cost Booklet_2713_11.csv
• 2713_CFPB Settlement Cost Booklet_2713_2.csv
• 2713_CFPB Settlement Cost Booklet_2713_3.csv
• 2713_CFPB Settlement Cost Booklet_2713_4.csv
• 2713_CFPB Settlement Cost Booklet_2713_5.csv
• 2713_CFPB Settlement Cost Booklet_2713_6.csv
• 2713_CFPB Settlement Cost Booklet_2713_7.csv
• 2713_CFPB Settlement Cost Booklet_2713_8.csv
• 2713_CFPB Settlement Cost Booklet_2713_9.csv

But instead i want to collect the values in this order.

• 2713_CFPB Settlement Cost Booklet_2713_1.csv
• 2713_CFPB Settlement Cost Booklet_2713_2.csv
• 2713_CFPB Settlement Cost Booklet_2713_3.csv
• 2713_CFPB Settlement Cost Booklet_2713_4.csv
• 2713_CFPB Settlement Cost Booklet_2713_5.csv
• 2713_CFPB Settlement Cost Booklet_2713_6.csv
• 2713_CFPB Settlement Cost Booklet_2713_7.csv
• 2713_CFPB Settlement Cost Booklet_2713_8.csv
• 2713_CFPB Settlement Cost Booklet_2713_9.csv
• 2713_CFPB Settlement Cost Booklet_2713_10.csv
• 2713_CFPB Settlement Cost Booklet_2713_11.csv

Appreciate help.

Answer 1

You can do:

• Get File name only using Path.GetFileNameWithoutExtension
• Split them based on _
• Get Last item
• Parse it using int.Parse or int.TryParse
• Use that value in OrderBy with LINQ

Code:

var output = path.OrderBy(p => 
                        int.TryParse(Path.GetFileNameWithoutExtension(p).Split('_').Last(), out temp) ?
                        temp : int.MaxValue);

If you need an array or List<T> as output then append ToArray() or ToList() to the query.