If there are really so many values that you can't put all of them in a
combobox (like thousands), I'd find another way to do it. You could put a
filtering combobox first, then the customer combobox next to it, with the
filter filled with the letters from A to Z, then load the customer combobox
based on the filter.  If THAT filtered list is small enough, you could make
it an autocomplete list.

Put a list of linklabels across the screen for each letter of the alphabet,
and when they click on one, load the customer combobox.

If you want them to be able to filter on more than one letter, put a textbox
on the left with a button called something like "GetCustomers" and load the
customer combobox based on that.

Capture the keypress event, restart a stopwatch every time they click a key
in the combobox, and when they stop for more than a couple of seconds, run
the query. This, of course, would be the most difficult.

You have to decide what it's worth, and what your customers are willing to
pay for.

RobinS.
GoldMail, Inc.
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