bind function in react js code example

Example 1: react bind function to component

class Foo extends Component {
  constructor(props) {
    super(props);
    this.handleClick = this.handleClick.bind(this);
  }
  handleClick() {
    console.log('Click happened');
  }
  render() {
    return <button onClick={this.handleClick}>Click Me</button>;
  }
}

Example 2: callback in react

import React, { useCallback } from 'react';

function MyComponent() {
  // handleClick is the same function object
  const handleClick = useCallback(() => {    console.log('Clicked!');  }, []);
  // ...
}

Example 3: react button onclick

import React from 'react';

function App() {

  function sayHello() {
    alert('Hello!');
  }
  
  return (
    <button onClick={sayHello}>
      Click me!
    </button>
  );
}

export default App;

Example 4: handling event in jsx

//Event hadling in react
function ActionLink() {
  function handleClick(e) {
    e.preventDefault();
    console.log('The link was clicked.');
  }

  return (
    <a href="#" onClick={handleClick}>
      Click me
    </a>
  );
}