Two questions: should I do client-side or server-side in terms of validation? Also, how would I verify that no textbox is blank/invalid...
<p>...with jquery/javascript?  I want to check and make sure that a value has been entered and that it's a number.</p>

<p>First - Is it a best practice to do validation on the client-side, server-side, or both?  Is this something that should be validated twice or is checking on the client-side enough?</p>

<p>Second - If client-side validation is the best way to go about this, how could I do this with javascript/jquery?  I assume that for the button that's clicked, I would assign its <code>onclientclick</code> equal to a javascript function.</p>
