You definitively want to check all input data. And take some time to figure out how to check it as well.

Don't try to refuse or ignore stuff that you won't accept. Doing that, you will continue to add more and more checks every time someone enters something you didn't think of.

Take the other approach: Define what you will accept and accept nothing but what you consider valid data.

We've even had some exitement here at the Monastery today concerning input data, when someone registered the new user name <!-- and many pages showed up as broken. As a result, the input data validation had to be improved.

"Livet är hårt" sa bonden.
"Grymt" sa grisen...

In reply to Re: Safe variables in CGI by Biker
in thread Safe variables in CGI by Stegalex

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