Check a range of checkboxes on a gridview in asp.net

I have a page with a gridview that has a checkbox column.

I also have a range selector (two drop-down-lists) that contain a start number and an end number - these numbers represent all the rows in the gridview.

I want to be able to "check" all the checkboxes in the gridview based upon the range selected in the two drop-down lists.

I have found methods that check all the boxes but not a range.

Does anybody know of how best to do this?

Thanks