Is Dirty

I'm doing a quick and dirty prototype app, with one simple detail edit
screen, so I've used simple own code to transfer values between controls and
data entity, deferring properly implementing data binding at a later
stage[1].  Now I want to know if the edited entity is 'dirty'.  My first
reaction is to serialise it on starting my edit, and then when closing the
form, and compare the two.  How do the experts here feel about this?