I beg to differ.

You cannot allow the server to trust that the client side is not tricking it, especially for ecommerce.

All form validation must happen at the server, and possibly, for a better user experience (think responsiveness), also validated with javascript.

I'd also like to note that inn my experience most the javascript validation I met really sucks. Just recently I had to fool an online purchase form which was trying to verify my CCN using javascript that calls a VB script function. I have MacOS X, and use Safari, which isn't VB script enabled.

The only way I could actually buy the thing is if i cheated the javascript. It was simple, too, i just entered the URL javascript:document.formname.submit().

-nuffin
zz zZ Z Z #!perl

In reply to Re^2: How do I write a CGI script with form validation? by nothingmuch
in thread How do I write a CGI script with form validation? by blazesixty

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