Dynamically-generated option list?

I need to present a list of options in dropdown list B
based on what the user selected in dropdown list A.
Both A and B content will be generated dynamically from
a database, similar to the way http://cars.com lets the user
select the make of a car, which in turn populates a list
of models. (That site itself is no help, since the
relevant functions don't appear in the source of the page.)

A URL of an appropriate Javascript tutorial or example
would be welcome. The tutorials I've found so far use
static option lists. I guess what I really need is to
see how an option list can be generated dynamically.
I've tried Googling for Javascript tutorials containing
"onChange", but haven't found anything useful yet.

--
Charles Packer
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re: Dynamically-generated option list?

On Mar 13, 12:34 am, Charles Packer <mail...@cpacker.orgwrote:http://www.javascripttoolbox.com/lib/dynamicoptionlist/

re: Dynamically-generated option list?

On Mar 12, 6:55 pm, VK <schools_r...@yahoo.comwrote:
Thanks. This seems to be exactly what I need for the
basic mechanics, but I need to access a database to re-populate the
child list each time the user selects a different option from the
parent list. I've learned through some Googling that Javascript
doesn't support SQL directly. I infer, however, that I can have a
Javascript function execute an external Perl script that would do the
SQL and return the results, though I haven't found
a tutorial/example yet that shows how to execute an
external program.

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Charles Packer
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re: Dynamically-generated option list?

On Mar 13, 11:28 am, Charles Packer <mail...@cpacker.orgwrote:Oops! I've gone through enough of one of the Javascript
tutorials at this point to see that, because Javascript
is client-side and Perl is server-side, it implies
an action -- however it is coded -- that will be just
like hitting a URL to get my new list content each time.
Sounds inefficient...Now, since I'll be generating the
page itself via a CGI call, I guess I could generate
all the possible lists (46 child lists of, at most,
a dozen entries each) as static Javascript code as part of that page.
Wish me luck...

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Charles Packer
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