I'm currently trying to get a FileSystemWatcher to work, as outlined in this question. During my research, I found a lot of answers and comments on this site describing the unreliability of this class. Instead, "polling" is mentioned in some places as a method of watching for changes, for example in this (very old) answer. My question is what that means exactly.

CodePudding user response：

Polling means here that you regularly read for instance the last write-time of the files you want to watch and test if there is a difference. you could even read the file contents and compare it with a previous verison. Polling just means that you actively do the comparison instead of being notified.

Polling is best avoided for its cost. But if needed then it is needed.

https://en.wikipedia.org/wiki/Polling_(computer_science)

Regarding FileSystemwatcher. It is not perfect but in my experience correct enough in the majority of the cases . I assume that all watchers in developer tools use that mechanism and it is for instance good enough there. I suggest to try it first for your purpose before polling.