Many desktop applications have user interface controls that allow a user to find matches for things as they type. This feature can be very useful for long lists of items such as states, countries, streets or product categories. Many web browsers implement this sort of functionality in their address bars. As you type, web site address matches that are part of a list of recently visited sites appear in a menu below the address bar. This reduces the amount of time it takes to access information.
Another place this is implemented is in HTML select menus. Unfortunately this only works with the first letter typed, it is not implemented in all browsers on all platforms and it doesn't shorten the list of choices to only matches.
Check also DMXzone's own Ajax AutoComplete Dreamweaver extension to get field auto completion right out of the box!
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