Runs before React applies the result of render to the document, and
returns an object to be given to componentDidUpdate. Useful for saving
things such as scroll position before render causes changes to it.
Note: the presence of this method prevents any of the deprecated
lifecycle events from running.
Runs before React applies the result of render to the document, and returns an object to be given to componentDidUpdate. Useful for saving things such as scroll position before render causes changes to it.
Note: the presence of this method prevents any of the deprecated lifecycle events from running.