React性能优化指南：如何提升前端应用的加载速度

// package.json
{
  "scripts": {
    "build": "react-scripts build"
  }
}

import React, { Suspense } from 'react';

const LazyComponent = React.lazy(() => import('./LazyComponent'));

function App() {
  return (
    <div>
      <Suspense fallback={<div>Loading...</div>}>
        <LazyComponent />
      </Suspense>
    </div>
  );
}

import React, { memo } from 'react';

const MyComponent = memo(props => {
  return <div>{props.text}</div>;
});

class MyComponent extends React.Component {
  shouldComponentUpdate(nextProps, nextState) {
    return nextProps.text !== this.props.text;
  }

  render() {
    return <div>{this.props.text}</div>;
  }
}

import React, { lazy, Suspense, memo } from 'react';

const LazyComponent = lazy(() => import('./LazyComponent'));

const MemoizedComponent = memo(props => {
  return (
    <Suspense fallback={<div>Loading...</div>}>
      <LazyComponent {...props} />
    </Suspense>
  );
});

import React, { useState, useEffect } from 'react';

function App() {
  const [data, setData] = useState([]);

  useEffect(() => {
    fetchData();
  }, []);

  const fetchData = async () => {
    const response = await fetch('https://api.example.com/data');
    const data = await response.json();
    setData(data);
  };

  return (
    <div>
      {data.map(item => (
        <div key={item.id}>{item.name}</div>
      ))}
    </div>
  );
}