Create a hidden input element in the form and set the value with javascript. Then it will be passed as a CGI parameter.

One other thing - You should also remember that some people will have JS off or blocked, so having a CGI only alternative is always recommended.

UPDATE: added caveat

grep

In reply to Re: Passing javascript variables to Perl CGI by grep
in thread Passing javascript variables to Perl CGI by Harch84

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