You should store anything of value server-side (usually in a database or session), but the other way of protecting those is including a signature as a hidden field in the form. Something like sha1(concatenate($longsecrettoken, %importantformfields)) should be enough (but I'm not a cryptographer so don't quote me on that).

In reply to Re: Modiying values in html form by Anonymous Monk
in thread Modiying values in html form by kiat

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