Creating a search box similar to facebook

I want to create a search box for my website where results are show as I a开发者_如何转开发m typing. The idea is that as people type something in, the user table will be searched for that username.

".TBL_USERS." is the table. The row would be username.

How would I go about doing this?

THankyou

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Check out jQuery UI Autocomplete widget, it should be what you want.