The best place would be in the browser - something that may be simplified using jQuery.
jQuery gridview plugins[
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Web applications split their execution/logic between browser (like FireFox or IE) and web server (like IIS).
To make anything happen server side the page has to perform some sort of communication with the server (like a postback, or calling a web service). So something (like a button) in the browser has to trigger that action.
Update
Work your way through:
http://msdn.microsoft.com/en-us/library/ms229601.aspx[
^]
Then go through:
http://www.asp.net/web-forms[
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This provides a thorough grounding on the basics of .Net development and asp.net.
You might also benefit from reading:
The Data Model Resource Book: A Library of Universal Data Models for All Enterprises, Revised Edition, Volume 1[
^]
Good luck :)
Regards
Espen Harlinn