Is Client-side JavaScript / jQuery form validation useless? [duplicate]

Question

Possible Duplicate:
JavaScript: client-side vs. server-side validation

There are a lot of JavaScript/jQuery client-side form validation scripts out there. But considering that it's client side, it's fairly easy to bypass the validation and submit a form with values that ignore the validation rules. The only solution is to also implement server-side validation as well in order to protect yourself.

Client-side jQuery validation is fun and it looks slick, but if you already have to implement server-side validation then what's the point of the client-side validation? It seems unnecessarily redundant and a waste of development time. Is it useless?

Also, are there any good ways to implement client-side validation that don't require server-side validation?

Answer 1

Client Side validation can always be bypassed. There's no way around this. Backend validation should always be used when dealing with sensitive information, writing to/reading from a db, or really anything that could be hacked.

Client side validation is just there because it's faster. Much rather know instantly that my email address wasn't formatted correctly than after I've submitted the form, the server checked it out, and sent something back.