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When useState update then map loop is not working in array inside of object in useState. React js

When useState update then map loop is not working in array inside of object in useState. React js

import { useState } from "react";
import React from "react";
function Check() {
const [Children, setChildren] = useState({data:[], otherdata:{}});
 function handleChange(){
 Children["data"] = [...Children["data"], Children["data"].length]
 setChildren(Children)
 alert(Children["data"])
  return (<React.Fragment>
    <div>Check</div>
    {Children["data"].map(data => <div>map</div>)}
    <button
     onClick={handleChange}
    >Add List</button>
  </React.Fragment>);
export default Check
                You need to update the actual object, not just the array inside of it, otherwise, you'll have a reference to the same object and react won't rerender: setChildren({...Children, data: [...Children.data, Children.data.length]})
– Nick Parsons
                Jul 11, 2021 at 6:51
  const [Children, setChildren] = useState({ data: [], otherdata: {} });
  function handleChange() {
    setChildren({
      ...Children,
      data: [...Children["data"], Children["data"].length],
  return (
    <React.Fragment>
      <div>Check</div>
      {Children.data.map((ele) => (
        <div>{ele}</div>
      <button onClick={handleChange}>Add List</button>
    </React.Fragment>
export default Check;

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