Can one detect document content changed?

[Ben Rush]

I'm sure there is something out there for this, but I want to detect
if document content has been changed for whatever reason.

Say someone creates a javascript function which, say, changes some
content of the document. I want to be able to intercept this event and
say "yes" or "no" to it, or, at least be able to be notified that a
change is about to happen or has just happened.

The "content" has to be anything about the page - basically if the
document content changes I want to know about it.

Does such a thing exist?

Thanks in advance,
Ben

[Brian Genisio]

Ben Rush wrote:

I'm sure there is something out there for this, but I want to detect
if document content has been changed for whatever reason.

Say someone creates a javascript function which, say, changes some
content of the document. I want to be able to intercept this event and
say "yes" or "no" to it, or, at least be able to be notified that a
change is about to happen or has just happened.

The "content" has to be anything about the page - basically if the
document content changes I want to know about it.

Does such a thing exist?

Thanks in advance,
Ben

Could you give an example for what you are trying to do? If you have
control of the page, don't you know what changes are being made? Even
if it is done by Javascript?

The situation seems confusing, so an actual example would be helpful.

Thanks :)
Brian