Answers for "use setstate in react"

how to use setstate

class App extends React.Component {

state = { count: 0 }

handleIncrement = () => {
  this.setState({ count: this.state.count + 1 })
}

handleDecrement = () => {
  this.setState({ count: this.state.count - 1 })
}
  render() {
    return (
      <div>
        <div>
          {this.state.count}
        </div>
        <button onClick={this.handleIncrement}>Increment by 1</button>
        <button onClick={this.handleDecrement}>Decrement by 1</button>
      </div>
    )
  }
}

state react

class Example extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      count: 0
    };
  }

  render() {
    return (
      <div>
        <p>You clicked {this.state.count} times</p>
        <button onClick={() => this.setState({ count: this.state.count + 1 })}>
          Click me
        </button>
      </div>
    );
  }
}

setstate in react

Functional Component
const [counter, setCounter] = useState(0);

setCouter(counter + 1);

react setState

this.setState({
      date: new Date()
    });

counter composant react

import React, { useState } from 'react';

function Example() {
  // Déclare une nouvelle variable d'état, que l'on va appeler « count »  const [count, setCount] = useState(0);
  return (
    <div>
      <p>Vous avez cliqué {count} fois</p>
      <button onClick={() => setCount(count + 1)}>
        Cliquez ici
      </button>
    </div>
  );
}

setState

@protected
void setState(VoidCallback fn) {
  if (_scopeKey.currentState != null) {
    _scopeKey.currentState!._routeSetState(fn);
  } else {
    // The route isn't currently visible, so we don't have to call its setState
    // method, but we do still need to call the fn callback, otherwise the state
    // in the route won't be updated!
    fn();
  }
}