What the most efficient way of monitoring changes to data on an ASP.Net form?
<p>I have an ASP.Net form and I want to send an email when the user changes their data. The email should only include data that has changed, and there are about 15 data fields total.</p>

<p>I don't want to use an ORM since I am updating a website that a 3rd party built for us, and all their data access calls go through a custom library of theirs.</p>

<p>The only ways to do this I can think of is</p>

<ul>
<li><p>Make another database call to get old values and compare the form values one-by-one. If they're different, append to the email.</p></li>
<li><p>Store original data somewhere when it's first loaded (hidden field, session, etc), and once again compare the data one field at a time and append the differences to an email</p></li>
<li><p>Have someone on SO tell me there's an easier and/or simpler way that I haven't thought of</p></li>
</ul>
