C# listbox select item on scrolling to it

I have a listbox with about 5 items : blank 1 2 3 4 5

(only one displayed on the GUI scroll at a time and user has to scroll to others) and based on the value selected I have to do a search . I am keeping the first item in the Collection property as blank since by default the first item in a listbox is Selected. Hence if the user doesn't select anything , it will do a search on blank and my regex will return ALL if the search is done on blank.

However , if the user selects one of the other entries , say 3 and then scrolls to another item , the new item is not registered unless the user clicks on it in the listbox .

I want the selection to be done on scroll .

1)Is there a better way to design this use case by using a different control ?

2) Can selection on scroll be done through properties as opposed to writing some piece of code on some Event handler like say "scrolled"