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Reactjs 通过函数声明设置状态_Reactjs_Setstate - Fatal编程技术网

Reactjs 通过函数声明设置状态

Reactjs 通过函数声明设置状态,reactjs,setstate,Reactjs,Setstate,无法通过函数声明setState。我不明白错在哪里 import React, { Component } from 'react'; export default class App extends Component { state = { text: ' ', }; render() { const text = () => { this.setState({ text: 'Good afternoon' }); }; re

无法通过函数声明setState。我不明白错在哪里

import React, { Component } from 'react';
export default class App extends Component {
  state = {
    text: ' ',
  };

  render() {
    const text = () => {
      this.setState({ text: 'Good afternoon' });
    };

    return(

    )
  }
}

函数和设置状态应在渲染生命周期之外。 更多信息:

设置状态指南:


请将函数文本置于渲染函数之外

export default class App extends Component {
state = {
    text: ' ',
};

//function in here
text = () => {
    this.setState({ text: 'Good afternoon' });
}


render() {

    return ()
}

}

无论如何,当我传递的函数文本超出渲染限制时,setState不起作用。

函数应该在渲染之外。请看你说它不工作是什么意思?请分享你的努力。
export default class App extends Component {
state = {
    text: ' ',
};

//function in here
text = () => {
    this.setState({ text: 'Good afternoon' });
}


render() {

    return ()
}