Validation Conrols: Client Side or Server Side?

Hi Folks,

I am just wondering if the validation controls, use javascript...or server side code behind...
Clearly, I would prefer it be server-side, because i'm concerned that a potential evil-doer could by-pass the validation, by turning off JS.
If the validation controls use JS --- can someone refer me to proper server side validation techniques (VB).

Thanks,

- Joel

 

 
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