Uniquely identify dynamic web pages
I am developing and app that needs to identify web pages, URL is the best criteria to do this, But for me it is not enough since there are lots of dynamically generated web pages (like ASP or PHP pages that can vary by time or by user).

Methods like hashing the entire web page to know if it has changed is costly and may or may not work.

Is it possible to do it? if yes what is the best way to do it?
Uniquely identify dynamic web pages
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I am developing and app that needs to identify web pages, URL is the best criteria to do this, But for me it is not enough since there are lots of dynamically generated web pages (like ASP or PHP pages that can vary by time or by user).

Methods like hashing the entire web page to know if it has changed is costly and may or may not work.

Is it possible to do it? if yes what is the best way to do it?