如何在React中使用钩子强制组件重新渲染?

考虑下面的钩子示例

   import { useState } from 'react';

   function Example() {
       const [count, setCount] = useState(0);

       return (
           <div>
               <p>You clicked {count} times</p>
               <button onClick={() => setCount(count + 1)}>
                  Click me
               </button>
          </div>
        );
     }

基本上，我们使用this.forceUpdate()方法强制组件立即在React类组件中重新渲染，如下例所示

    class Test extends Component{
        constructor(props){
             super(props);
             this.state = {
                 count:0,
                 count2: 100
             }
             this.setCount = this.setCount.bind(this);//how can I do this with hooks in functional component 
        }
        setCount(){
              let count = this.state.count;
                   count = count+1;
              let count2 = this.state.count2;
                   count2 = count2+1;
              this.setState({count});
              this.forceUpdate();
              //before below setState the component will re-render immediately when this.forceUpdate() is called
              this.setState({count2: count
        }

        render(){
              return (<div>
                   <span>Count: {this.state.count}></span>. 
                   <button onClick={this.setCount}></button>
                 </div>
        }
 }

但我的问题是，我如何才能强制上述功能组件重新渲染立即与挂钩?

当前回答

const useForceRender = () => {
  const [, forceRender] = useReducer(x => !x, true)
  return forceRender
}

使用

function Component () {
  const forceRender = useForceRender() 
  useEffect(() => {
    // ...
    forceRender()
  }, [])

2021-10-15 11:12:52

其他回答

React Hooks FAQ官方解决方案的forceUpdate:

const [_, forceUpdate] = useReducer((x) => x + 1, 0);
// usage
<button onClick={forceUpdate}>Force update</button>

工作示例

2020-01-05 17:25:40

const useForceRender = () => {
  const [, forceRender] = useReducer(x => !x, true)
  return forceRender
}

使用

function Component () {
  const forceRender = useForceRender() 
  useEffect(() => {
    // ...
    forceRender()
  }, [])

2021-10-15 11:12:52

@MinhKha的回答:

使用useReducer可以更简洁:

const [, forceUpdate] = useReducer(x => x + 1, 0);

用法: forceUpdate() -没有参数的清洁器

2019-10-13 04:47:20

你可以(ab)利用React在JSX代码中不打印布尔值的事实，使用普通钩子强制渲染

// create a hook
const [forceRerender, setForceRerender] = React.useState(true);

// ...put this line where you want to force a rerender
setForceRerender(!forceRerender);

// ...make sure that {forceRerender} is "visible" in your js code
// ({forceRerender} will not actually be visible since booleans are
// not printed, but updating its value will nonetheless force a
// rerender)
return (
  <div>{forceRerender}</div>
)

2019-07-11 11:31:37

你可以像这样简单地定义useState:

const [, forceUpdate] = React.useState(0);

和用法:forceUpdate(n => !n)

希望这对你有所帮助!

2019-07-03 04:13:50

如何在React中使用钩子强制组件重新渲染?

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