react 中操作数组出现的问题

IDE在线版

import { useEffect, useState } from 'react';

export default function App() {
  const [instruct, setInstruct] = useState([0, 1, 2]);

  const increase = () => {
    console.log('lastArr', instruct);
    const length = instruct.length - 1;
    const _instruct = instruct.slice();
    const target = ++_instruct[length];
    console.log('现在的问题：', target);
    _instruct.push(target);
    setInstruct(_instruct);
    console.log('currentArr', _instruct);
  };

  return (
    <div>
      <button onClick={increase}>Click</button>
    </div>
  );
}

这里的 ++[0,1,2][2] 看样子会修改原数组的中2 索引的值然后在赋值给 target

xiaochengzi6 / Blog

react 中操作数组出现的问题 #55