Entry Point Configuration

import React from 'react';
import ReactDOM from 'react-dom';
import App from './App';

ReactDOM.render(<App />, document.getElementById('app'));

Main Application Component

import React from 'react';
import Home from './Home';

export default function App() {
  return (
    <div>
      <Home />
    </div>
  );
}

State Management with useState Hook

import React, { useState } from 'react';

const Counter = () => {
  const [counterValue, updateCounter] = useState(0);
  const [dataItems, setDataItems] = useState([10, 20, 30, 40]);
  
  return (
    <div>
      <button onClick={() => updateCounter(counterValue + 1)}>
        Increment
      </button>
      <span>{counterValue}</span>
      <button onClick={() => setDataItems([50, 60, 70, 80])}>
        Update List
      </button>
      {dataItems.map((element, idx) => (
        <div key={idx}>{element}</div>
      ))}
    </div>
  );
};

export default Counter;

Side Effects with useEffect Hook

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

const DataComponent = () => {
  const [carouselData, setCarouselData] = useState([]);
  const [productData, setProductData] = useState([]);

  useEffect(() => {
    axios.get('/api/carousel').then(response => {
      setCarouselData(response.data.data);
    });
  });

  useEffect(() => {
    axios.get('/api/products').then(response => {
      setProductData(response.data.data);
    });
  });

  return (
    <div>
      Carousel Items:
      {carouselData.map(item => (
        <div key={item.id}>{item.imageUrl}</div>
      ))}
      Product List:
      {productData.map(product => (
        <div key={product.id}>{product.name}</div>
      ))}
    </div>
  );
};

export default DataComponent;

Condisional Effect Executino

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

const ControlledEffects = () => {
  const [carouselItems, setCarouselItems] = useState([]);
  const [products, setProducts] = useState([]);

  useEffect(() => {
    axios.get('/api/carousel').then(response => {
      setCarouselItems(response.data.data);
    });
  }, [carouselItems]);

  useEffect(() => {
    axios.get('/api/products').then(response => {
      setProducts(response.data.data);
    });
  }, []);

  return (
    <div>
      {carouselItems.map(item => (
        <div key={item.id}>{item.imageUrl}</div>
      ))}
      {products.map(product => (
        <div key={product.id}>{product.name}</div>
      ))}
    </div>
  );
};

export default ControlledEffects;

Custom Hook Implementation

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

const useAuthStatus = () => {
  const [authState, setAuthState] = useState('unauthorized');
  
  useEffect(() => {
    if (localStorage.getItem('authToken') === 'valid') {
      setAuthState('authorized');
    } else {
      setAuthState('unauthorized');
    }
  }, [authState]);
  
  return authState;
};

const AuthComponent = () => {
  const authStatus = useAuthStatus();

  return (
    <div>
      {authStatus === 'authorized' ? (
        <p>Authenticated User</p>
      ) : (
        <p>Please Log In</p>
      )}
    </div>
  );
};

export default AuthComponent;