I have a CGI script that I'm developing that dynamically creates form elements along with the HTML content, based on items in a database. Think of it this way -- the page you're looking at was created by pulling this message from a MySQL database. One of the items on this page, right below this message, is probably a Radio Button allowing you to vote on this post. The source code for the HTML will identify this radio button with something similar to <INPUT type=radio name='vote__37894' value='1'> where 37894 is a unique identifier tied to this record.

Now my CGI isn't going to know to look for vote__37894 or even $query->param('vote__37894'). But if I get a list of all the variables I'm returning, using @names = $ query->param; then I should be able to pattern match against "vote__*" and do something from there based on the wildcard.

So my question is, if I'm passing other things, like comment__37894, how can I build a variable name based on variable content? If a variable exists named vote__foo then I want to update my database with comment__foo where foo is the record number in my database. How do I concatinate "comment__" and the value of "foo", and use that concatinated string as a variable name?

Hoping some of that made sense...

In reply to Variable variable names by cei

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