Form Processing

ASP has no ideea of what is going on in the client browser until he hit the submit button, but JScript is powerfull enough for handling even some complex form checking. The only downsize to JScript is that some people believe that it does horrible things to their computers and turn it down. Even some firewalls may interfere with that.

If it is very important and you cannot rely on JScript, I would do n intermediary temporary page and only in this page I would place the Submit button. That is:

Te user is filling in the form and has 2 choices: Reset and Check. After he use the check button it is taken into a page that checks the values of the form and point him to correct them (if necessary). And only here he has the option of submitting the form. Or, of course, to correct the problems.

One of the things I am keen on in asp.net 2.0 where exactly that is possible. returning results from a db based on a form without posting the form. It's called Script Callback by implementing ICallbackEventHandler. Essentially I think it puts some dynamic javascript on the page that accepts DOM responens from the server. Theoretically you can implement something like that in any language thus I think it'll get quite complicated and you have to ensure the browser supports DOM