functionProfile({ userId }){// ✅ Good: comment包括其他的state在key改变时会自动的重置const[comment, setComment] = useState('');// ...} 通常,React在同一组件的同一个地方渲染时,React会保留状态。 四、当props改变时重置部分state 可能也有一些场景,比如说你只希望在props改变时,只修改部分的state,...
[1]https://react.dev/learn/thinking-in-react#step-3-find-the-minimal-but-complete-representation-of-ui-state [2]https://react.dev/reference/react/useState#storing-information-from-previous-renders [3]https://react.dev/reference/react/useState#updating-objects-and-arrays-in-state [4]https://...
In short, if you are using the second parameter[]then you need to put all the variable (state or not) that you rely on. So in your case, if you want to have access to thescrollstate variable then you need to put[scroll]:)
// component rerendered haveSameNumberOfValues: true showResult: true startValues: 3 endValues: 6 // useEffet is called (because endValues was 3 and become 6), and since inside useEffect you are updating the state (setShowResult(x) and setHaveSameNumberOfValues(y)) the component rerender...
setbolidata改变状态中的值。下一次组件呈现时，useState将从状态中提取新值并将其分配给bolidata。但是...
无论使用setInterval()还是setTimeout()，函数的执行环境会被设置成window，也就是说在函数内使用this...
1. The infinite loop and side-effect updating state Let's say you want to create a component having an input field, and also display how many times the user changed that input. Here's a possible implementation of <CountInputChanges> component: import { useEffect, useState } from 'react';...
1.将getUsers移到组件外部。1.让所有东西都在一次使用中运行效果（一次，在装载时）1.坚持使用async/...
By implementing a condition that identifies if the error is due to an abort action, we can avoid updating the state in such scenarios, ensuring smoother error management and component lifecycle handling: useEffect(()=>{constcontroller=newAbortController();constsignal=controller.signal;fetch(API,{sign...
useEffect(() => { // No infinite loop setState(count + 1); }, [whenToUpdateValue]);Alternatively, you can also use a reference. Updating a reference doesn't trigger a re-rendering:countRef.current++;Another common recipe for an infinite loop is to use an object as a dependency of ...