Supports IComparer

Users may provide an IComparer object to customize the sort behavior. With IComparer objects, it is possible to do things like always position empty values at the bottom of the sorts.

The following is a graphic detailing the use of a custom IComparer object. In the picture, column B has values like b73, b31, etc. By default, this column would be sorted alphabetically. But with a custom sort, a user may strip off the leading 'b', and have the column displayed numerically sorted ignoring the 'b'. The picture shows both the default and custom sort results.