I'm writing an email add-in program that needs to flag emails that contain dropbox file share links. I've searched here at the Community. I did find there is no way right now to detect invalid urls.
I am looking for something close to that post, but my question is not the same because assumptions can be made about the url when testing it. An url that was valid until the given file was renamed/deleted/moved at one time is still a Dropbox file share url, it just may not work (and dead links do not matter).
What text can I use to parse string as a test for a Dropbox file share url?