search and filter stocknumber binding from sql

Question

HI,

 

       I want to make a search and filter box where i can search the stock number by typing first or middle or last  letter and based on that i can update the stock quantity.Here i have 300 stock numbers where i can bind from sql db.

          how can i make dropdown list as search box or  Is there any other process using asp.net c# and sql db.