intellisense in a asp textbox

I want to implement a intellisense kind of feature in a normal text box in which the user will type some text in a textbox and keep getting intellisense help to complete the current word.
for example in my database i create one table xxxx in that i created one field locations.it contains 100 locaton names.
when i am enter one location name in textbox i want intellisence kind of future for my textbox i want to pick up 100 location names from my database table xxxx
plz give me any sample code.......