How to sort an array of FileInfo[] C#

Question

I have the following code

DirectoryInfo taskDirectory = new DirectoryInfo(this.taskDirectoryPath);
FileInfo[] taskFiles = taskDirectory.GetFiles("*" + blah + "*.xml");

I would like to sort the list by filename.

How is this done, as quickly and easily as possible using .net v2.

Thank you

Answer 1

Comparison<FileInfo> comparison = new Comparison<FileInfo>(delegate(FileInfo a, FileInfo b)
{
    return String.Compare(a.Name, b.Name);
});

Array.Sort(taskFiles, comparison);

But anyway I think the result of GetFiles is already sorted by name...

Answer 2

Call Array.Sort, passing in a comparison delegate:

Array.Sort(taskFiles, delegate(FileInfo f1, FileInfo f2) {
    return f1.Name.CompareTo(f2.Name);
});

In C# 3 this becomes slightly simpler:

Array.Sort(taskFiles, (f1, f2) => f1.Name.CompareTo(f2.Name));

Or you can use a StringComparer if you want to use a case-insensitive sort order:

Array.Sort(taskFiles,
           (x, y) => StringComparer.OrdinalIgnoreCase.Compare(x.Name, y.Name));

(or use string.Compare(x.Name, y.Name, true), or any of the many other ways of comparing strings :)

Answer 3

Array.Sort(taskFiles, delegate (FileInfo x, FileInfo y) {
    return string.Compare(x.Name,y.Name);
});

Answer 4

http://mattandchristy.com/post/2008/02/Custom-Sorting-In-C-Sharp.aspx

It looks like the default sort is by filename, have you tested that? Anyway the example I linked to is similar to the other suggestions here, just a little more documentation to it :o)

Answer 5

    public class FileComparer : IComparer
        {
         public enum CompareBy
         {
          Name /* a-z */,
          LastWriteTime /* oldest to newest */,
          CreationTime  /* oldest to newest */,
          LastAccessTime /* oldest to newest */,
          FileSize /* smallest first */,

         }
         // default comparison
         int _CompareBy = (int)CompareBy.Name;
         public FileComparer()
         {
         }

         public FileComparer(CompareBy compareBy)
         {
          _CompareBy = (int)compareBy;
         }
         int IComparer.Compare( object x, object y )
         {
          int output = 0;
          DirectoryInfo file1 = new DirectoryInfo(x.ToString());
          DirectoryInfo file2 = new DirectoryInfo(y.ToString());
          switch(_CompareBy)
          {
           case (int)CompareBy.LastWriteTime:
            output = DateTime.Compare(file1.LastWriteTime, file2.LastWriteTime);
            break;
           case (int)CompareBy.CreationTime:
            output = DateTime.Compare(file1.CreationTime, file2.CreationTime);
            break;
           case (int)CompareBy.LastAccessTime:
            output = DateTime.Compare(file1.LastAccessTime, file2.LastAccessTime);
            break;
    //     case (int)CompareBy.FileSize:
    //      output = Convert.ToInt32(file1.Length - file2.Length);
    //      break;
           case (int)CompareBy.Name:
           default:
            output = (new CaseInsensitiveComparer()).Compare( file1.Name, file2.Name );
            break;
          }
          return output;
         }
        }

///////////////////////////////////
ArrayList list=new ArrayList();   
      string folder = @"D:\DVRData\ICICI\Transaction\21-Dec-08\08_51_23_2231";
      string[] files = Directory.GetFiles(folder);   
      IComparer comp = new FileComparer(FileComparer.CompareBy.CreationTime);
      Array.Sort(files, comp);
      foreach(string file in files)
      {
       list.Add(file);
      }