what is useState in react js code example

Example 1: react usestate

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: update state in useState hook

// declare state using useState hook.
// someState is set to someInitialState
const [someState, setSomeState] = useState(someInitialState);

// setSomeState updates the current state 
setSomeState(someOtherState);

Example 3: usestate in react

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 4: react usestate

function Counter({initialCount}) {
  const [count, setCount] = useState(initialCount);
  return (
    <>
      Count: {count}
      <button onClick={() => setCount(initialCount)}>Reset</button>
      <button onClick={() => setCount(prevCount => prevCount - 1)}>-</button>
      <button onClick={() => setCount(prevCount => prevCount + 1)}>+</button>
    </>
  );
}

Example 5: useState

import React, { useState } from 'react';
function Example() {
  const [variable, callforupdate] = useState(defaulttwhatever);// <-- this it
  return (
    <div></div>
    );
}