sorting when name includes letters and numeric digits

Question

I have following array

[0] = GB_22_T0001.jpg
[1] = GB_22_T0002.jpg
[2] = GB_22_T0003.jpg
[3] = GB_22_T0006.jpg
[4] = GB_22_T0007.jpg
[5] = GB_22_T0008.jpg
[6] = GB_22_T0009.jpg
[7] = GB_22_T00010.jpg
[8] = GB_22_T00011.jpg
[9] = GB_22_T00012.jpg
[10] = GB_22_T00013.jpg

I have put this items in a listbox and noticed that 'GB_22_T00010' comes straight after 'GB_22_T0001' instead of 'GB_22_T0002'

Seems to be a common issue with c# but cannot find a common answer to the problem.

I tried sorting the array with Array.sort(data) and also tried LinQ's OrderBy method but none of them helps.

Anyone with a solution?

Answer 1

This is my code to sort a string having both alpha and numeric characters.

First, this extension method :

public static IEnumerable<string> AlphanumericSort(this IEnumerable<string> me)
{
    return me.OrderBy(x => Regex.Replace(x, @"\d+", m => m.Value.PadLeft(50, '0')));
}

Then, simply use it anywhere in your code like this :

List<string> test = new List<string>() { "The 1st", "The 12th", "The 2nd" };
test = test.AlphanumericSort();

How does it works ? By replaceing with zeros :

  Original  | Regex Replace |      The      |   Returned
    List    | Apply PadLeft |    Sorting    |     List
            |               |               |
 "The 1st"  |  "The 001st"  |  "The 001st"  |  "The 1st"
 "The 12th" |  "The 012th"  |  "The 002nd"  |  "The 2nd"
 "The 2nd"  |  "The 002nd"  |  "The 012th"  |  "The 12th"

Works with multiples numbers :

 Alphabetical Sorting | Alphanumeric Sorting
                      |
 "Page 21, Line 42"   | "Page 3, Line 7"
 "Page 21, Line 5"    | "Page 3, Line 32"
 "Page 3, Line 32"    | "Page 21, Line 5"
 "Page 3, Line 7"     | "Page 21, Line 42"

Hope that's will help.