Have you tried the links I posted before.
These ones especially has an example in how the alphanumerical sorting is done.
http://madebits.com/articles/numsort/index.phpsee Example 2 - Ordering Items in a ListView Control.
http://dotnetperls.com/alphanumeric-sortingSee item 2. Implementing IComparer interface
It implement a comparator for alphanumeric sorting in C#. You just need to replace
private CaseInsensitiveComparer ObjectCompare;
with this new class AlphanumComparatorFast:
private AlphanumComparatorFast ObjectCompare;
public class AlphanumComparatorFast : IComparer