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Run useEffect Only Once :React

Harish Sankaramanchi on February 13, 2020

If you want to run an effect and clean it up only once (on mount and unmount), you can pass an empty array ([]) as a second argument. This tells R...
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Alex Lohr •

Also if you only want to run it on unmount, you can use

useEffect(() => onUnmountHandler, [])
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onUnmountHandler will then be called after the component unmounts.