react use code example

Example 1: react state hooks

import React, { useState } from 'react';

function Example() {
  // Declare a new state variable, which we'll call "count"  
  const [count, setCount] = useState(0);
  
  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}

Example 2: useEffect

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

function Example() {
  const [count, setCount] = useState(0);

  // Similar to componentDidMount and componentDidUpdate:
  useEffect(() => {
    // Update the document title using the browser API
    document.title = `You clicked ${count} times`;
  });

  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}

Example 3: useeffect react

useEffect(() => {
  window.addEventListener('mousemove', () => {});

  // returned function will be called on component unmount 
  return () => {
    window.removeEventListener('mousemove', () => {})
  }
}, [])

Example 4: usestate hook

import React, { useState } from 'react';

function Example() {
  // Declare a new state variable, which we'll call "count"  
  const [count, setCount] = useState(0);
  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}

Example 5: react js documentation

//With node and npm already installed for basic start

npx create-react-app my-app-name

// if you want to use npm 

npx create-react-app my-app-name --npm

//if you want to use typescript 

npx create-react-app my-app-name --template typescript

yarn start // app will be hosted on localhost:3000

/* start making changes at ./my-app-name/src/App.js
	React documentation: https://reactjs.org/docs/hello-world.html
*/

Example 6: document.title you clicked count times

import React, { useState, useEffect } from 'react';
function Example() {
  const [count, setCount] = useState(0);

  useEffect(() => {    document.title = `You clicked ${count} times`;  });
  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}