import { useCallback, useEffect } from 'react'; import { off, on } from './misc/util'; const useBeforeUnload = (enabled: boolean | (() => boolean) = true, message?: string) => { const handler = useCallback( (event: BeforeUnloadEvent) => { const finalEnabled = typeof enabled === 'function' ? enabled() : true; if (!finalEnabled) { return; } event.preventDefault(); if (message) { event.returnValue = message; } return message; }, [enabled, message] ); useEffect(() => { if (!enabled) { return; } on(window, 'beforeunload', handler); return () => off(window, 'beforeunload', handler); }, [enabled, handler]); }; export default useBeforeUnload;