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@uiw/react-native

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import { useRef, useEffect } from 'react'; /** * 获取上一轮的 props 或 state * How to get the previous props or state? * https://reactjs.org/docs/hooks-faq.html#how-to-get-the-previous-props-or-state * @example * ```js * function Counter() { * const [count, setCount] = useState(0); * const prevCount = usePrevious(count); * return <h1>Now: {count}, before: {prevCount}</h1>; * } * ``` */ export function usePrevious(value) { const ref = useRef(); useEffect(() => { ref.current = value; }); return ref.current; }